diff --git a/migrations/migrate_2026-05-02.py b/migrations/migrate_2026-05-02.py
new file mode 100644
index 0000000..1c5a61f
--- /dev/null
+++ b/migrations/migrate_2026-05-02.py
@@ -0,0 +1,251 @@
+"""Migration 2026-05-02: User-Delete-Fix + unlimited_budget + Audit/Brute-Force Tabellen.
+
+Aenderungen:
+  (A) ON DELETE SET NULL fuer incidents.created_by, magic_links.user_id, network_analyses.created_by
+  (B) Neue Spalte licenses.unlimited_budget (mit Backfill)
+  (C) Neue Tabellen portal_audit_log, portal_login_attempts
+
+Idempotent: jeder Schritt prueft, ob er bereits ausgefuehrt wurde.
+Vorher: Backup der DB anlegen!
+"""
+import sqlite3
+import sys
+
+DB_PATH = "/home/claude-dev/osint-data/osint.db"
+
+
+def has_on_delete_set_null(db, table, column):
+    """Prueft, ob die ON DELETE SET NULL Klausel bereits gesetzt ist."""
+    row = db.execute(
+        "SELECT sql FROM sqlite_master WHERE type='table' AND name=?", (table,)
+    ).fetchone()
+    if not row:
+        return False
+    sql = row[0]
+    return "ON DELETE SET NULL" in sql.upper() and column in sql
+
+
+def column_exists(db, table, column):
+    cols = [r[1] for r in db.execute("PRAGMA table_info(" + table + ")").fetchall()]
+    return column in cols
+
+
+def table_exists(db, name):
+    return db.execute(
+        "SELECT 1 FROM sqlite_master WHERE type='table' AND name=?", (name,)
+    ).fetchone() is not None
+
+
+def recreate_table(db, name, new_create_sql, indexes):
+    """Recreate-Pattern: alte Spalten in neue Tabelle kopieren."""
+    print("  - Recreate " + name + "...")
+    cols_old = [r[1] for r in db.execute("PRAGMA table_info(" + name + ")").fetchall()]
+    db.execute(new_create_sql.replace("TABLE " + name, "TABLE " + name + "_new"))
+    cols_new = [r[1] for r in db.execute("PRAGMA table_info(" + name + "_new)").fetchall()]
+    common = [c for c in cols_old if c in cols_new]
+    cols_csv = ", ".join(common)
+    db.execute("INSERT INTO " + name + "_new (" + cols_csv + ") SELECT " + cols_csv + " FROM " + name)
+    db.execute("DROP TABLE " + name)
+    db.execute("ALTER TABLE " + name + "_new RENAME TO " + name)
+    for idx_sql in indexes:
+        db.execute(idx_sql)
+
+
+def main():
+    db = sqlite3.connect(DB_PATH)
+    db.row_factory = sqlite3.Row
+
+    counts_before = {}
+    for t in ["incidents", "magic_links", "network_analyses", "licenses",
+              "users", "organizations", "sources"]:
+        counts_before[t] = db.execute("SELECT COUNT(*) FROM " + t).fetchone()[0]
+    print("Counts vor Migration:")
+    for t, n in counts_before.items():
+        print("  " + t + ": " + str(n))
+    print()
+
+    db.execute("PRAGMA foreign_keys=OFF")
+    db.execute("BEGIN")
+
+    try:
+        print("(A) ON DELETE SET NULL fuer 3 Tabellen")
+
+        if not has_on_delete_set_null(db, "incidents", "created_by"):
+            recreate_table(
+                db, "incidents",
+                """CREATE TABLE incidents (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    title TEXT NOT NULL,
+    description TEXT,
+    status TEXT DEFAULT 'active',
+    refresh_mode TEXT DEFAULT 'manual',
+    refresh_interval INTEGER DEFAULT 15,
+    retention_days INTEGER DEFAULT 0,
+    summary TEXT,
+    created_by INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    type TEXT DEFAULT 'adhoc',
+    sources_json TEXT,
+    international_sources INTEGER DEFAULT 1,
+    visibility TEXT DEFAULT 'public',
+    tenant_id INTEGER REFERENCES organizations(id),
+    notify_email_summary INTEGER DEFAULT 0,
+    notify_email_contradiction INTEGER DEFAULT 0,
+    notify_email_status_change INTEGER DEFAULT 0,
+    include_telegram INTEGER DEFAULT 0,
+    telegram_categories TEXT DEFAULT NULL,
+    category_labels TEXT,
+    executive_summary TEXT,
+    refresh_start_time TEXT,
+    latest_developments TEXT
+)""",
+                [
+                    "CREATE INDEX idx_incidents_tenant_status ON incidents(tenant_id, status)",
+                ],
+            )
+        else:
+            print("  - incidents: bereits ON DELETE SET NULL, skip")
+
+        if not has_on_delete_set_null(db, "magic_links", "user_id"):
+            recreate_table(
+                db, "magic_links",
+                """CREATE TABLE magic_links (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    email TEXT NOT NULL,
+    token TEXT UNIQUE NOT NULL,
+    code TEXT NOT NULL,
+    purpose TEXT NOT NULL DEFAULT 'login',
+    user_id INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    is_used INTEGER DEFAULT 0,
+    expires_at TIMESTAMP NOT NULL,
+    ip_address TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+)""",
+                [],
+            )
+        else:
+            print("  - magic_links: bereits ON DELETE SET NULL, skip")
+
+        if not has_on_delete_set_null(db, "network_analyses", "created_by"):
+            recreate_table(
+                db, "network_analyses",
+                """CREATE TABLE network_analyses (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    name TEXT NOT NULL,
+    status TEXT DEFAULT 'pending',
+    entity_count INTEGER DEFAULT 0,
+    relation_count INTEGER DEFAULT 0,
+    data_hash TEXT,
+    last_generated_at TIMESTAMP,
+    tenant_id INTEGER REFERENCES organizations(id),
+    created_by INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+)""",
+                [],
+            )
+        else:
+            print("  - network_analyses: bereits ON DELETE SET NULL, skip")
+
+        print("")
+        print("(B) licenses.unlimited_budget Spalte")
+        if not column_exists(db, "licenses", "unlimited_budget"):
+            db.execute("ALTER TABLE licenses ADD COLUMN unlimited_budget INTEGER DEFAULT 0")
+            print("  - Spalte angelegt")
+            res = db.execute(
+                "UPDATE licenses SET unlimited_budget=1 "
+                "WHERE credits_total IS NULL OR cost_per_credit IS NULL OR cost_per_credit=0"
+            )
+            print("  - Backfill: " + str(res.rowcount) + " Lizenzen auf unlimited gesetzt")
+        else:
+            print("  - bereits vorhanden, skip")
+
+        print("")
+        print("(C) portal_audit_log + portal_login_attempts")
+        if not table_exists(db, "portal_audit_log"):
+            db.execute("""
+                CREATE TABLE portal_audit_log (
+                    id INTEGER PRIMARY KEY AUTOINCREMENT,
+                    ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+                    admin_id INTEGER,
+                    admin_username TEXT,
+                    ip TEXT,
+                    action TEXT NOT NULL,
+                    resource_type TEXT,
+                    resource_id INTEGER,
+                    before_json TEXT,
+                    after_json TEXT
+                )
+            """)
+            db.execute("CREATE INDEX idx_audit_ts ON portal_audit_log(ts DESC)")
+            db.execute("CREATE INDEX idx_audit_admin ON portal_audit_log(admin_id)")
+            db.execute("CREATE INDEX idx_audit_resource ON portal_audit_log(resource_type, resource_id)")
+            print("  - portal_audit_log angelegt")
+        else:
+            print("  - portal_audit_log bereits vorhanden, skip")
+
+        if not table_exists(db, "portal_login_attempts"):
+            db.execute("""
+                CREATE TABLE portal_login_attempts (
+                    id INTEGER PRIMARY KEY AUTOINCREMENT,
+                    ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+                    ip TEXT NOT NULL,
+                    username TEXT NOT NULL,
+                    success INTEGER NOT NULL DEFAULT 0
+                )
+            """)
+            db.execute("CREATE INDEX idx_login_lookup ON portal_login_attempts(ip, username, ts)")
+            print("  - portal_login_attempts angelegt")
+        else:
+            print("  - portal_login_attempts bereits vorhanden, skip")
+
+        db.execute("COMMIT")
+        db.execute("PRAGMA foreign_keys=ON")
+
+        print("")
+        print("=== Verifikation ===")
+        ok = True
+        for t, n in counts_before.items():
+            n_after = db.execute("SELECT COUNT(*) FROM " + t).fetchone()[0]
+            status = "OK" if n_after == n else "MISMATCH (" + str(n) + " -> " + str(n_after) + ")"
+            print("  " + t + ": " + str(n_after) + " " + status)
+            if n_after != n:
+                ok = False
+        for t, c in [("incidents", "created_by"), ("magic_links", "user_id"),
+                     ("network_analyses", "created_by")]:
+            on_del = has_on_delete_set_null(db, t, c)
+            print("  " + t + "." + c + " ON DELETE SET NULL: " + str(on_del))
+            if not on_del:
+                ok = False
+        col_ok = column_exists(db, "licenses", "unlimited_budget")
+        print("  licenses.unlimited_budget: " + str(col_ok))
+        if not col_ok:
+            ok = False
+        for t in ["portal_audit_log", "portal_login_attempts"]:
+            t_ok = table_exists(db, t)
+            print("  Tabelle " + t + ": " + str(t_ok))
+            if not t_ok:
+                ok = False
+
+        if ok:
+            print("")
+            print("Alle Checks OK")
+            return 0
+        else:
+            print("")
+            print("FEHLER: Mindestens ein Check fehlgeschlagen")
+            return 1
+
+    except Exception as e:
+        db.execute("ROLLBACK")
+        db.execute("PRAGMA foreign_keys=ON")
+        print("")
+        print("FEHLER: " + type(e).__name__ + ": " + str(e))
+        raise
+
+    finally:
+        db.close()
+
+
+if __name__ == "__main__":
+    sys.exit(main())
diff --git a/src/audit.py b/src/audit.py
new file mode 100644
index 0000000..eeb3630
--- /dev/null
+++ b/src/audit.py
@@ -0,0 +1,106 @@
+"""Audit-Log Helper.
+
+Schreibt Eintraege in portal_audit_log mit before/after-JSON.
+Diff-Helper filtert auf veraenderte Felder, um Speicher zu sparen.
+"""
+import json
+import logging
+from typing import Optional
+
+import aiosqlite
+from fastapi import Request
+
+logger = logging.getLogger("verwaltung.audit")
+
+
+def get_client_ip(request: Optional[Request]) -> str:
+    """IP aus X-Forwarded-For (Nginx) oder direkt aus Connection.
+
+    Nginx setzt X-Forwarded-For mit der echten Client-IP.
+    Falls nicht vorhanden, fallback auf request.client.host.
+    """
+    if request is None:
+        return ""
+    xff = request.headers.get("x-forwarded-for")
+    if xff:
+        # Erste IP in der Kette ist die echte Client-IP
+        return xff.split(",")[0].strip()
+    real = request.headers.get("x-real-ip")
+    if real:
+        return real.strip()
+    if request.client:
+        return request.client.host or ""
+    return ""
+
+
+def diff(before: Optional[dict], after: Optional[dict]) -> Optional[dict]:
+    """Filtert auf veraenderte Felder. Bei CREATE/DELETE: voller Datensatz."""
+    if before is None or after is None:
+        return None
+    changes = {}
+    keys = set(before.keys()) | set(after.keys())
+    for k in keys:
+        bv = before.get(k)
+        av = after.get(k)
+        if bv != av:
+            changes[k] = {"old": bv, "new": av}
+    return changes if changes else None
+
+
+def _to_json(d: Optional[dict]) -> Optional[str]:
+    if d is None:
+        return None
+    try:
+        return json.dumps(d, default=str, ensure_ascii=False)
+    except Exception as e:
+        logger.warning("audit JSON-Serialisierung fehlgeschlagen: %s", e)
+        return json.dumps({"_error": str(e)})
+
+
+async def log_action(
+    db: aiosqlite.Connection,
+    admin: Optional[dict],
+    ip: str,
+    action: str,
+    resource_type: Optional[str] = None,
+    resource_id: Optional[int] = None,
+    before: Optional[dict] = None,
+    after: Optional[dict] = None,
+) -> None:
+    """Schreibt einen Audit-Eintrag.
+
+    action: 'create' | 'update' | 'delete' | 'login_success' | 'login_failed' | 'login_blocked'
+    resource_type: 'organization' | 'user' | 'license' | 'source' | 'admin' | 'auth'
+    """
+    admin_id = admin.get("id") if admin else None
+    admin_username = admin.get("username") if admin else None
+
+    # Bei UPDATE: nur Diff speichern, sonst vollen Datensatz
+    if action == "update" and before is not None and after is not None:
+        d = diff(before, after)
+        if d is None:
+            # Keine Aenderung -> nicht loggen
+            return
+        before_json = _to_json({k: v["old"] for k, v in d.items()})
+        after_json = _to_json({k: v["new"] for k, v in d.items()})
+    else:
+        before_json = _to_json(before)
+        after_json = _to_json(after)
+
+    try:
+        await db.execute(
+            """INSERT INTO portal_audit_log
+               (admin_id, admin_username, ip, action, resource_type, resource_id, before_json, after_json)
+               VALUES (?, ?, ?, ?, ?, ?, ?, ?)""",
+            (admin_id, admin_username, ip, action, resource_type, resource_id, before_json, after_json),
+        )
+        await db.commit()
+    except Exception as e:
+        logger.error("audit log_action fehlgeschlagen: %s", e)
+
+
+async def row_to_dict(db: aiosqlite.Connection, table: str, row_id: int) -> Optional[dict]:
+    """Holt Datensatz als Dict (fuer before/after-Snapshot)."""
+    cursor = await db.execute(f"SELECT * FROM {table} WHERE id = ?", (row_id,))
+    row = await cursor.fetchone()
+    return dict(row) if row else None
diff --git a/src/main.py b/src/main.py
index dee5e40..bc12811 100644
--- a/src/main.py
+++ b/src/main.py
@@ -2,7 +2,7 @@
 import logging
 from contextlib import asynccontextmanager
 
-from fastapi import FastAPI, Depends, HTTPException, status
+from fastapi import FastAPI, Depends, HTTPException, status, Request
 from fastapi.staticfiles import StaticFiles
 from fastapi.responses import FileResponse
 
@@ -10,7 +10,8 @@ from config import STATIC_DIR, PORT
 from database import db_dependency
 from auth import verify_password, create_token
 from models import LoginRequest, TokenResponse
-from routers import organizations, licenses, users, dashboard, sources, token_usage
+from routers import organizations, licenses, users, dashboard, sources, token_usage, audit
+from audit import log_action, get_client_ip
 
 import aiosqlite
 
@@ -20,6 +21,11 @@ logging.basicConfig(
 )
 logger = logging.getLogger("verwaltung")
 
+# Brute-Force-Schutz
+MAX_FAILED_ATTEMPTS = 5
+BLOCK_WINDOW_MINUTES = 15
+PURGE_AFTER_HOURS = 24
+
 
 @asynccontextmanager
 async def lifespan(app: FastAPI):
@@ -41,25 +47,84 @@ app.include_router(users.router)
 app.include_router(dashboard.router)
 app.include_router(sources.router)
 app.include_router(token_usage.router)
+app.include_router(audit.router)
 
 
 # --- Login ---
 @app.post("/api/auth/login", response_model=TokenResponse)
 async def login(
     data: LoginRequest,
+    request: Request,
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
+    ip = get_client_ip(request)
+    username = data.username.strip()
+
+    # Alte Login-Versuche purgen (LRU-Style, einmal pro Anfrage)
+    await db.execute(
+        f"DELETE FROM portal_login_attempts WHERE ts < datetime('now', '-{PURGE_AFTER_HOURS} hours')"
+    )
+
+    # Brute-Force-Check: Anzahl Fehlversuche fuer (ip, username) im Zeitfenster
+    cursor = await db.execute(
+        f"""SELECT COUNT(*) AS cnt FROM portal_login_attempts
+            WHERE ip = ? AND username = ? AND success = 0
+            AND ts > datetime('now', '-{BLOCK_WINDOW_MINUTES} minutes')""",
+        (ip, username),
+    )
+    failed_count = (await cursor.fetchone())["cnt"]
+
+    if failed_count >= MAX_FAILED_ATTEMPTS:
+        await log_action(
+            db, admin=None, ip=ip, action="login_blocked",
+            resource_type="auth",
+            after={"username": username, "failed_attempts": failed_count},
+        )
+        await db.commit()
+        raise HTTPException(
+            status_code=status.HTTP_429_TOO_MANY_REQUESTS,
+            detail=f"Zu viele Fehlversuche. Bitte {BLOCK_WINDOW_MINUTES} Minuten warten.",
+            headers={"Retry-After": str(BLOCK_WINDOW_MINUTES * 60)},
+        )
+
+    # Auth-Pruefung
     cursor = await db.execute(
         "SELECT id, username, password_hash FROM portal_admins WHERE username = ?",
-        (data.username,),
+        (username,),
     )
     admin = await cursor.fetchone()
-    if not admin or not verify_password(data.password, admin["password_hash"]):
+    auth_ok = bool(admin and verify_password(data.password, admin["password_hash"]))
+
+    # Versuch in Tabelle eintragen (fuer Brute-Force-Tracking)
+    await db.execute(
+        "INSERT INTO portal_login_attempts (ip, username, success) VALUES (?, ?, ?)",
+        (ip, username, 1 if auth_ok else 0),
+    )
+    await db.commit()
+
+    if not auth_ok:
+        admin_dict = (
+            {"id": admin["id"], "username": admin["username"]} if admin else None
+        )
+        await log_action(
+            db, admin=admin_dict, ip=ip, action="login_failed",
+            resource_type="auth",
+            after={"username": username},
+        )
         raise HTTPException(
             status_code=status.HTTP_401_UNAUTHORIZED,
             detail="Ungueltige Zugangsdaten",
         )
 
+    # Erfolg
+    await log_action(
+        db,
+        admin={"id": admin["id"], "username": admin["username"]},
+        ip=ip,
+        action="login_success",
+        resource_type="auth",
+    )
+
     token = create_token(admin["id"], admin["username"])
     return TokenResponse(access_token=token, username=admin["username"])
 
diff --git a/src/models.py b/src/models.py
index 763af9f..b9b8390 100644
--- a/src/models.py
+++ b/src/models.py
@@ -46,6 +46,7 @@ class LicenseCreate(BaseModel):
     credits_total: Optional[int] = None
     cost_per_credit: Optional[float] = None
     budget_warning_percent: Optional[int] = Field(default=80, ge=1, le=100)
+    unlimited_budget: bool = False
 
 
 class LicenseResponse(BaseModel):
@@ -62,6 +63,7 @@ class LicenseResponse(BaseModel):
     credits_used: Optional[float] = None
     cost_per_credit: Optional[float] = None
     budget_warning_percent: Optional[int] = None
+    unlimited_budget: bool = False
     created_at: str
     globe_access: bool = False
     network_access: bool = False
diff --git a/src/routers/audit.py b/src/routers/audit.py
new file mode 100644
index 0000000..405c700
--- /dev/null
+++ b/src/routers/audit.py
@@ -0,0 +1,115 @@
+"""Audit-Log Read-only Endpoint."""
+import json
+import logging
+from typing import Optional
+from fastapi import APIRouter, Depends, HTTPException
+from auth import get_current_admin
+from database import db_dependency
+import aiosqlite
+
+logger = logging.getLogger("verwaltung.audit_router")
+router = APIRouter(prefix="/api/audit-log", tags=["audit"])
+
+
+def _parse_json(s: Optional[str]):
+    if not s:
+        return None
+    try:
+        return json.loads(s)
+    except Exception:
+        return s
+
+
+@router.get("")
+async def list_audit(
+    action: Optional[str] = None,
+    resource_type: Optional[str] = None,
+    admin_id: Optional[int] = None,
+    from_ts: Optional[str] = None,
+    to_ts: Optional[str] = None,
+    limit: int = 200,
+    offset: int = 0,
+    admin: dict = Depends(get_current_admin),
+    db: aiosqlite.Connection = Depends(db_dependency),
+):
+    """Audit-Log-Eintraege auflisten mit Filter + Pagination."""
+    if limit < 1 or limit > 1000:
+        limit = 200
+    if offset < 0:
+        offset = 0
+
+    where = []
+    params = []
+    if action:
+        where.append("action = ?")
+        params.append(action)
+    if resource_type:
+        where.append("resource_type = ?")
+        params.append(resource_type)
+    if admin_id is not None:
+        where.append("admin_id = ?")
+        params.append(admin_id)
+    if from_ts:
+        where.append("ts >= ?")
+        params.append(from_ts)
+    if to_ts:
+        where.append("ts <= ?")
+        params.append(to_ts)
+
+    where_sql = ("WHERE " + " AND ".join(where)) if where else ""
+
+    # Total count fuer Pagination
+    cursor = await db.execute(f"SELECT COUNT(*) AS cnt FROM portal_audit_log {where_sql}", params)
+    total = (await cursor.fetchone())["cnt"]
+
+    # Daten
+    cursor = await db.execute(
+        f"""SELECT id, ts, admin_id, admin_username, ip, action,
+                   resource_type, resource_id, before_json, after_json
+            FROM portal_audit_log {where_sql}
+            ORDER BY ts DESC, id DESC
+            LIMIT ? OFFSET ?""",
+        params + [limit, offset],
+    )
+    rows = await cursor.fetchall()
+
+    items = []
+    for r in rows:
+        items.append({
+            "id": r["id"],
+            "ts": r["ts"],
+            "admin_id": r["admin_id"],
+            "admin_username": r["admin_username"],
+            "ip": r["ip"],
+            "action": r["action"],
+            "resource_type": r["resource_type"],
+            "resource_id": r["resource_id"],
+            "before": _parse_json(r["before_json"]),
+            "after": _parse_json(r["after_json"]),
+        })
+
+    return {
+        "items": items,
+        "total": total,
+        "limit": limit,
+        "offset": offset,
+    }
+
+
+@router.get("/distinct")
+async def get_distinct_values(
+    admin: dict = Depends(get_current_admin),
+    db: aiosqlite.Connection = Depends(db_dependency),
+):
+    """Distinct-Werte fuer Filter-Dropdowns."""
+    cursor = await db.execute("SELECT DISTINCT action FROM portal_audit_log ORDER BY action")
+    actions = [r["action"] for r in await cursor.fetchall()]
+    cursor = await db.execute("SELECT DISTINCT resource_type FROM portal_audit_log WHERE resource_type IS NOT NULL ORDER BY resource_type")
+    resource_types = [r["resource_type"] for r in await cursor.fetchall()]
+    cursor = await db.execute("SELECT DISTINCT admin_id, admin_username FROM portal_audit_log WHERE admin_id IS NOT NULL ORDER BY admin_username")
+    admins = [{"id": r["admin_id"], "username": r["admin_username"]} for r in await cursor.fetchall()]
+    return {
+        "actions": actions,
+        "resource_types": resource_types,
+        "admins": admins,
+    }
diff --git a/src/routers/licenses.py b/src/routers/licenses.py
index 2e15eb2..c83d427 100644
--- a/src/routers/licenses.py
+++ b/src/routers/licenses.py
@@ -1,9 +1,10 @@
 """Lizenz-CRUD."""
 from datetime import datetime, timedelta, timezone
-from fastapi import APIRouter, Depends, HTTPException, status
+from fastapi import APIRouter, Depends, HTTPException, status, Request
 from models import LicenseCreate, LicenseResponse
 from auth import get_current_admin
 from database import db_dependency
+from audit import log_action, get_client_ip, row_to_dict
 import aiosqlite
 
 router = APIRouter(prefix="/api/licenses", tags=["licenses"])
@@ -28,21 +29,35 @@ async def list_licenses(
 @router.post("", response_model=LicenseResponse, status_code=status.HTTP_201_CREATED)
 async def create_license(
     data: LicenseCreate,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
-    # Org pruefen
     cursor = await db.execute(
         "SELECT id FROM organizations WHERE id = ?", (data.organization_id,)
     )
     if not await cursor.fetchone():
         raise HTTPException(status_code=404, detail="Organisation nicht gefunden")
 
-    # Bestehende aktive Lizenz widerrufen
-    await db.execute(
-        "UPDATE licenses SET status = 'revoked' WHERE organization_id = ? AND status = 'active'",
+    # Bestehende aktive Lizenz widerrufen + Snapshot fuer Audit
+    cursor = await db.execute(
+        "SELECT * FROM licenses WHERE organization_id = ? AND status = 'active'",
         (data.organization_id,),
     )
+    revoked_lics = [dict(r) for r in await cursor.fetchall()]
+    if revoked_lics:
+        await db.execute(
+            "UPDATE licenses SET status = 'revoked' WHERE organization_id = ? AND status = 'active'",
+            (data.organization_id,),
+        )
+        for old_lic in revoked_lics:
+            new_lic = dict(old_lic)
+            new_lic["status"] = "revoked"
+            await log_action(
+                db, admin, get_client_ip(request),
+                action="update", resource_type="license", resource_id=old_lic["id"],
+                before=old_lic, after=new_lic,
+            )
 
     now = datetime.now(timezone.utc)
     valid_from = now.isoformat()
@@ -57,49 +72,74 @@ async def create_license(
     elif data.license_type == "annual":
         valid_until = (now + timedelta(days=365)).isoformat()
 
+    # Bei unlimited_budget: Credits/Cost/Budget ignorieren
+    if data.unlimited_budget:
+        token_budget_usd = None
+        credits_total = None
+        cost_per_credit = None
+    else:
+        token_budget_usd = data.token_budget_usd
+        credits_total = data.credits_total
+        cost_per_credit = data.cost_per_credit
+
     cursor = await db.execute(
         """INSERT INTO licenses (organization_id, license_type, max_users, valid_from, valid_until, status,
-           token_budget_usd, credits_total, cost_per_credit, budget_warning_percent)
-           VALUES (?, ?, ?, ?, ?, 'active', ?, ?, ?, ?)""",
+           token_budget_usd, credits_total, cost_per_credit, budget_warning_percent, unlimited_budget)
+           VALUES (?, ?, ?, ?, ?, 'active', ?, ?, ?, ?, ?)""",
         (data.organization_id, data.license_type, data.max_users, valid_from, valid_until,
-         data.token_budget_usd, data.credits_total, data.cost_per_credit, data.budget_warning_percent),
+         token_budget_usd, credits_total, cost_per_credit, data.budget_warning_percent,
+         1 if data.unlimited_budget else 0),
     )
+    lic_id = cursor.lastrowid
     await db.commit()
 
-    cursor = await db.execute("SELECT * FROM licenses WHERE id = ?", (cursor.lastrowid,))
-    return dict(await cursor.fetchone())
+    cursor = await db.execute("SELECT * FROM licenses WHERE id = ?", (lic_id,))
+    new_lic = dict(await cursor.fetchone())
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="create", resource_type="license", resource_id=lic_id,
+        after=new_lic,
+    )
+    return new_lic
 
 
 @router.put("/{license_id}/revoke")
 async def revoke_license(
     license_id: int,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
-    cursor = await db.execute("SELECT * FROM licenses WHERE id = ?", (license_id,))
-    lic = await cursor.fetchone()
-    if not lic:
+    before = await row_to_dict(db, "licenses", license_id)
+    if not before:
         raise HTTPException(status_code=404, detail="Lizenz nicht gefunden")
 
     await db.execute("UPDATE licenses SET status = 'revoked' WHERE id = ?", (license_id,))
     await db.commit()
+
+    after = await row_to_dict(db, "licenses", license_id)
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="update", resource_type="license", resource_id=license_id,
+        before=before, after=after,
+    )
     return {"ok": True}
 
 
 @router.put("/{license_id}/extend")
 async def extend_license(
     license_id: int,
+    request: Request,
     days: int = 365,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
-    cursor = await db.execute("SELECT * FROM licenses WHERE id = ?", (license_id,))
-    lic = await cursor.fetchone()
-    if not lic:
+    before = await row_to_dict(db, "licenses", license_id)
+    if not before:
         raise HTTPException(status_code=404, detail="Lizenz nicht gefunden")
 
-    if lic["valid_until"]:
-        base = datetime.fromisoformat(lic["valid_until"])
+    if before.get("valid_until"):
+        base = datetime.fromisoformat(before["valid_until"])
     else:
         base = datetime.now(timezone.utc)
 
@@ -109,6 +149,13 @@ async def extend_license(
         (new_until, license_id),
     )
     await db.commit()
+
+    after = await row_to_dict(db, "licenses", license_id)
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="update", resource_type="license", resource_id=license_id,
+        before=before, after=after,
+    )
     return {"ok": True, "valid_until": new_until}
 
 
diff --git a/src/routers/organizations.py b/src/routers/organizations.py
index 58142a7..58a2b56 100644
--- a/src/routers/organizations.py
+++ b/src/routers/organizations.py
@@ -1,9 +1,10 @@
 """Organisations-CRUD."""
 from datetime import datetime, timezone
-from fastapi import APIRouter, Depends, HTTPException, status
+from fastapi import APIRouter, Depends, HTTPException, status, Request
 from models import OrgCreate, OrgUpdate, OrgResponse
 from auth import get_current_admin
 from database import db_dependency
+from audit import log_action, get_client_ip, row_to_dict
 import aiosqlite
 
 router = APIRouter(prefix="/api/orgs", tags=["organizations"])
@@ -40,10 +41,10 @@ async def list_organizations(
 @router.post("", response_model=OrgResponse, status_code=status.HTTP_201_CREATED)
 async def create_organization(
     data: OrgCreate,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
-    # Slug-Duplikat pruefen
     cursor = await db.execute("SELECT id FROM organizations WHERE slug = ?", (data.slug,))
     if await cursor.fetchone():
         raise HTTPException(status_code=400, detail="Slug bereits vergeben")
@@ -53,10 +54,17 @@ async def create_organization(
         "INSERT INTO organizations (name, slug, is_active, created_at, updated_at) VALUES (?, ?, 1, ?, ?)",
         (data.name, data.slug, now, now),
     )
+    org_id = cursor.lastrowid
     await db.commit()
 
-    cursor = await db.execute("SELECT * FROM organizations WHERE id = ?", (cursor.lastrowid,))
-    return await _enrich_org(db, await cursor.fetchone())
+    cursor = await db.execute("SELECT * FROM organizations WHERE id = ?", (org_id,))
+    new_row_obj = await cursor.fetchone()
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="create", resource_type="organization", resource_id=org_id,
+        after=dict(new_row_obj),
+    )
+    return await _enrich_org(db, new_row_obj)
 
 
 @router.get("/{org_id}", response_model=OrgResponse)
@@ -76,12 +84,12 @@ async def get_organization(
 async def update_organization(
     org_id: int,
     data: OrgUpdate,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
-    cursor = await db.execute("SELECT * FROM organizations WHERE id = ?", (org_id,))
-    row = await cursor.fetchone()
-    if not row:
+    before = await row_to_dict(db, "organizations", org_id)
+    if not before:
         raise HTTPException(status_code=404, detail="Organisation nicht gefunden")
 
     updates = {}
@@ -97,6 +105,13 @@ async def update_organization(
         await db.execute(f"UPDATE organizations SET {set_clause} WHERE id = ?", values)
         await db.commit()
 
+    after = await row_to_dict(db, "organizations", org_id)
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="update", resource_type="organization", resource_id=org_id,
+        before=before, after=after,
+    )
+
     cursor = await db.execute("SELECT * FROM organizations WHERE id = ?", (org_id,))
     return await _enrich_org(db, await cursor.fetchone())
 
@@ -104,13 +119,18 @@ async def update_organization(
 @router.delete("/{org_id}", status_code=status.HTTP_204_NO_CONTENT)
 async def delete_organization(
     org_id: int,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
-    cursor = await db.execute("SELECT * FROM organizations WHERE id = ?", (org_id,))
-    if not await cursor.fetchone():
+    before = await row_to_dict(db, "organizations", org_id)
+    if not before:
         raise HTTPException(status_code=404, detail="Organisation nicht gefunden")
 
-    # Kaskadierendes Loeschen
     await db.execute("DELETE FROM organizations WHERE id = ?", (org_id,))
     await db.commit()
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="delete", resource_type="organization", resource_id=org_id,
+        before=before,
+    )
diff --git a/src/routers/sources.py b/src/routers/sources.py
index 3c06602..5f13666 100644
--- a/src/routers/sources.py
+++ b/src/routers/sources.py
@@ -6,12 +6,13 @@ import logging
 # Monitor-Source-Rules verfügbar machen
 sys.path.insert(0, "/home/claude-dev/AegisSight-Monitor/src")
 
-from fastapi import APIRouter, Depends, HTTPException, status
+from fastapi import APIRouter, Depends, HTTPException, status, Request
 from fastapi.responses import StreamingResponse
 from pydantic import BaseModel, Field
 from typing import Optional
 from auth import get_current_admin
 from database import db_dependency
+from audit import log_action, get_client_ip, row_to_dict
 import aiosqlite
 
 sys.path.insert(0, os.path.join('/home/claude-dev/AegisSight-Monitor/src'))
@@ -65,6 +66,7 @@ async def list_global_sources(
 @router.post("/global", status_code=201)
 async def create_global_source(
     data: GlobalSourceCreate,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
@@ -86,16 +88,24 @@ async def create_global_source(
            VALUES (?, ?, ?, ?, ?, ?, ?, 'system', NULL)""",
         (data.name, data.url, data.domain, data.source_type, data.category, data.status, data.notes),
     )
+    src_id = cursor.lastrowid
     await db.commit()
 
-    cursor = await db.execute("SELECT * FROM sources WHERE id = ?", (cursor.lastrowid,))
-    return dict(await cursor.fetchone())
+    cursor = await db.execute("SELECT * FROM sources WHERE id = ?", (src_id,))
+    new_src = dict(await cursor.fetchone())
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="create", resource_type="source", resource_id=src_id,
+        after=new_src,
+    )
+    return new_src
 
 
 @router.put("/global/{source_id}")
 async def update_global_source(
     source_id: int,
     data: GlobalSourceUpdate,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
@@ -106,13 +116,14 @@ async def update_global_source(
     row = await cursor.fetchone()
     if not row:
         raise HTTPException(status_code=404, detail="Grundquelle nicht gefunden")
+    before = dict(row)
 
     updates = {}
     for field, value in data.model_dump(exclude_none=True).items():
         updates[field] = value
 
     if not updates:
-        return dict(row)
+        return before
 
     set_clause = ", ".join(f"{k} = ?" for k in updates)
     values = list(updates.values()) + [source_id]
@@ -120,24 +131,38 @@ async def update_global_source(
     await db.commit()
 
     cursor = await db.execute("SELECT * FROM sources WHERE id = ?", (source_id,))
-    return dict(await cursor.fetchone())
+    after = dict(await cursor.fetchone())
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="update", resource_type="source", resource_id=source_id,
+        before=before, after=after,
+    )
+    return after
 
 
 @router.delete("/global/{source_id}", status_code=204)
 async def delete_global_source(
     source_id: int,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
     """Grundquelle loeschen."""
     cursor = await db.execute(
-        "SELECT id FROM sources WHERE id = ? AND tenant_id IS NULL", (source_id,)
+        "SELECT * FROM sources WHERE id = ? AND tenant_id IS NULL", (source_id,)
     )
-    if not await cursor.fetchone():
+    row = await cursor.fetchone()
+    if not row:
         raise HTTPException(status_code=404, detail="Grundquelle nicht gefunden")
+    before = dict(row)
 
     await db.execute("DELETE FROM sources WHERE id = ?", (source_id,))
     await db.commit()
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="delete", resource_type="source", resource_id=source_id,
+        before=before,
+    )
 
 
 @router.get("/tenant")
@@ -159,6 +184,7 @@ async def list_tenant_sources(
 @router.post("/tenant/{source_id}/promote")
 async def promote_to_global(
     source_id: int,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
@@ -169,6 +195,7 @@ async def promote_to_global(
         raise HTTPException(status_code=404, detail="Quelle nicht gefunden")
     if row["tenant_id"] is None:
         raise HTTPException(status_code=400, detail="Bereits eine Grundquelle")
+    before = dict(row)
 
     if row["url"]:
         cursor = await db.execute(
@@ -185,7 +212,13 @@ async def promote_to_global(
     await db.commit()
 
     cursor = await db.execute("SELECT * FROM sources WHERE id = ?", (source_id,))
-    return dict(await cursor.fetchone())
+    after = dict(await cursor.fetchone())
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="update", resource_type="source", resource_id=source_id,
+        before=before, after=after,
+    )
+    return after
 
 
 
@@ -267,6 +300,7 @@ async def discover_source_endpoint(
 @router.post("/discover/add")
 async def add_discovered_sources(
     feeds: list[dict],
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
@@ -282,6 +316,7 @@ async def add_discovered_sources(
 
     added = 0
     skipped = 0
+    added_ids = []
     for feed in feeds:
         if not feed.get("url"):
             continue
@@ -290,11 +325,12 @@ async def add_discovered_sources(
             continue
 
         domain = feed.get("domain", "")
-        await db.execute(
+        cur = await db.execute(
             """INSERT INTO sources (name, url, domain, source_type, category, status, added_by, tenant_id)
                VALUES (?, ?, ?, 'rss_feed', ?, 'active', 'system', NULL)""",
             (feed["name"], feed["url"], domain, feed.get("category", "sonstige")),
         )
+        added_ids.append(cur.lastrowid)
         existing_urls.add(feed["url"])
         added += 1
 
@@ -315,6 +351,13 @@ async def add_discovered_sources(
             added += 1
 
     await db.commit()
+    if added_ids:
+        await log_action(
+            db, admin, get_client_ip(request),
+            action="create", resource_type="source",
+            after={"discovered_add": {"count": added, "ids": added_ids,
+                                       "domain": feeds[0].get("domain") if feeds else None}},
+        )
     return {"added": added, "skipped": skipped}
 
 
@@ -394,6 +437,7 @@ class SuggestionAction(BaseModel):
 async def update_suggestion(
     suggestion_id: int,
     action: SuggestionAction,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
@@ -478,6 +522,14 @@ async def update_suggestion(
         (new_status, suggestion_id),
     )
     await db.commit()
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="update", resource_type="source",
+        resource_id=suggestion.get("source_id"),
+        before={"suggestion_id": suggestion_id, "status": "pending"},
+        after={"suggestion_id": suggestion_id, "status": new_status,
+               "result_action": result_action},
+    )
     return {"status": new_status, "action": result_action}
 
 
diff --git a/src/routers/token_usage.py b/src/routers/token_usage.py
index c586635..af02c81 100644
--- a/src/routers/token_usage.py
+++ b/src/routers/token_usage.py
@@ -1,9 +1,10 @@
 """Token-Usage & Budget-Verwaltung."""
 import logging
 from datetime import datetime
-from fastapi import APIRouter, Depends, HTTPException
+from fastapi import APIRouter, Depends, HTTPException, Request
 from auth import get_current_admin
 from database import get_db
+from audit import log_action, get_client_ip, row_to_dict
 
 logger = logging.getLogger("verwaltung.token_usage")
 router = APIRouter(prefix="/api/token-usage", tags=["Token-Usage"])
@@ -15,10 +16,10 @@ async def get_usage_overview(admin=Depends(get_current_admin)):
     db = await get_db()
     try:
         cursor = await db.execute("""
-            SELECT 
+            SELECT
                 o.id, o.name, o.slug,
                 l.credits_total, l.credits_used, l.cost_per_credit,
-                l.token_budget_usd, l.budget_warning_percent,
+                l.token_budget_usd, l.budget_warning_percent, l.unlimited_budget,
                 COALESCE(SUM(r.total_cost_usd), 0) as total_cost,
                 COALESCE(SUM(r.input_tokens), 0) as total_input_tokens,
                 COALESCE(SUM(r.output_tokens), 0) as total_output_tokens,
@@ -30,17 +31,18 @@ async def get_usage_overview(admin=Depends(get_current_admin)):
             GROUP BY o.id
         """)
         rows = await cursor.fetchall()
-        
+
         result = []
         for row in rows:
             credits_total = row["credits_total"] or 0
             credits_used = row["credits_used"] or 0
-            credits_remaining = max(0, int(credits_total - credits_used)) if credits_total else None
-            percent_used = round((credits_used / credits_total) * 100, 1) if credits_total and credits_total > 0 else None
+            unlimited = bool(row["unlimited_budget"])
+            credits_remaining = None if unlimited else (max(0, int(credits_total - credits_used)) if credits_total else None)
+            percent_used = None if unlimited else (round((credits_used / credits_total) * 100, 1) if credits_total and credits_total > 0 else None)
             budget_usd = row["token_budget_usd"]
             cost = row["total_cost"]
-            budget_percent = round((cost / budget_usd) * 100, 1) if budget_usd and budget_usd > 0 else None
-            
+            budget_percent = None if unlimited else (round((cost / budget_usd) * 100, 1) if budget_usd and budget_usd > 0 else None)
+
             result.append({
                 "org_id": row["id"],
                 "org_name": row["name"],
@@ -53,6 +55,7 @@ async def get_usage_overview(admin=Depends(get_current_admin)):
                 "total_cost_usd": round(cost, 2),
                 "budget_percent_used": budget_percent,
                 "budget_warning_percent": row["budget_warning_percent"] or 80,
+                "unlimited_budget": unlimited,
                 "total_input_tokens": row["total_input_tokens"],
                 "total_output_tokens": row["total_output_tokens"],
                 "total_api_calls": row["total_api_calls"],
@@ -73,7 +76,7 @@ async def get_org_usage(org_id: int, admin=Depends(get_current_admin)):
             "SELECT * FROM token_usage_monthly WHERE organization_id = ? ORDER BY year_month DESC",
             (org_id,))
         rows = await cursor.fetchall()
-        
+
         return [{
             "year_month": row["year_month"],
             "source": row["source"] if "source" in row.keys() else "monitor",
@@ -95,12 +98,11 @@ async def get_org_current_usage(org_id: int, admin=Depends(get_current_admin)):
     db = await get_db()
     try:
         year_month = datetime.now().strftime("%Y-%m")
-        
+
         cursor = await db.execute(
             "SELECT * FROM token_usage_monthly WHERE organization_id = ? AND year_month = ?",
             (org_id, year_month))
         usage_rows = await cursor.fetchall()
-        # Summe ueber alle Sources
         usage = {
             "input_tokens": sum(r["input_tokens"] for r in usage_rows),
             "output_tokens": sum(r["output_tokens"] for r in usage_rows),
@@ -108,7 +110,6 @@ async def get_org_current_usage(org_id: int, admin=Depends(get_current_admin)):
             "api_calls": sum(r["api_calls"] for r in usage_rows),
             "refresh_count": sum(r["refresh_count"] for r in usage_rows),
         }
-        # Per-Source Aufschluesselung
         usage_by_source = {}
         for r in usage_rows:
             src = r["source"] if "source" in r.keys() else "monitor"
@@ -119,15 +120,16 @@ async def get_org_current_usage(org_id: int, admin=Depends(get_current_admin)):
                 "api_calls": r["api_calls"],
                 "refresh_count": r["refresh_count"],
             }
-        
+
         cursor = await db.execute(
-            "SELECT credits_total, credits_used, cost_per_credit, token_budget_usd, budget_warning_percent FROM licenses WHERE organization_id = ? AND status = 'active' ORDER BY id DESC LIMIT 1",
+            "SELECT credits_total, credits_used, cost_per_credit, token_budget_usd, budget_warning_percent, unlimited_budget FROM licenses WHERE organization_id = ? AND status = 'active' ORDER BY id DESC LIMIT 1",
             (org_id,))
         lic = await cursor.fetchone()
-        
+
+        unlimited = bool(lic["unlimited_budget"]) if lic else False
         credits_total = lic["credits_total"] if lic else None
         credits_used = lic["credits_used"] if lic else 0
-        
+
         return {
             "year_month": year_month,
             "usage": {
@@ -139,10 +141,11 @@ async def get_org_current_usage(org_id: int, admin=Depends(get_current_admin)):
             },
             "usage_by_source": usage_by_source,
             "budget": {
+                "unlimited_budget": unlimited,
                 "credits_total": credits_total,
                 "credits_used": round(credits_used, 1) if credits_used else 0,
-                "credits_remaining": max(0, int(credits_total - credits_used)) if credits_total else None,
-                "credits_percent_used": round((credits_used / credits_total) * 100, 1) if credits_total and credits_total > 0 else None,
+                "credits_remaining": None if unlimited else (max(0, int(credits_total - credits_used)) if credits_total else None),
+                "credits_percent_used": None if unlimited else (round((credits_used / credits_total) * 100, 1) if credits_total and credits_total > 0 else None),
                 "token_budget_usd": lic["token_budget_usd"] if lic else None,
                 "cost_per_credit": lic["cost_per_credit"] if lic else None,
                 "budget_warning_percent": lic["budget_warning_percent"] if lic else 80,
@@ -153,33 +156,52 @@ async def get_org_current_usage(org_id: int, admin=Depends(get_current_admin)):
 
 
 @router.put("/budget/{license_id}")
-async def update_budget(license_id: int, data: dict, admin=Depends(get_current_admin)):
-    """Budget einer Lizenz setzen/ändern."""
+async def update_budget(license_id: int, data: dict, request: Request, admin=Depends(get_current_admin)):
+    """Budget einer Lizenz setzen/aendern."""
     db = await get_db()
     try:
-        cursor = await db.execute("SELECT id FROM licenses WHERE id = ?", (license_id,))
-        if not await cursor.fetchone():
+        before = await row_to_dict(db, "licenses", license_id)
+        if not before:
             raise HTTPException(status_code=404, detail="Lizenz nicht gefunden")
-        
+
         fields = []
         values = []
         for key in ("token_budget_usd", "credits_total", "cost_per_credit", "budget_warning_percent"):
             if key in data:
                 fields.append(f"{key} = ?")
                 values.append(data[key])
-        
+
         if "credits_used" in data:
             fields.append("credits_used = ?")
             values.append(data["credits_used"])
-        
+
+        if "unlimited_budget" in data:
+            fields.append("unlimited_budget = ?")
+            values.append(1 if data["unlimited_budget"] else 0)
+
         if not fields:
             raise HTTPException(status_code=400, detail="Keine Felder zum Aktualisieren")
-        
+
         values.append(license_id)
         await db.execute(f"UPDATE licenses SET {', '.join(fields)} WHERE id = ?", values)
         await db.commit()
-        
-        logger.info(f"Budget für Lizenz {license_id} aktualisiert: {data}")
-        return {"ok": True}
+
+        after = await row_to_dict(db, "licenses", license_id)
+        await log_action(
+            db, admin, get_client_ip(request),
+            action="update", resource_type="license", resource_id=license_id,
+            before=before, after=after,
+        )
+
+        # Konsistenz-Hinweis
+        warning = None
+        if after and not after.get("unlimited_budget"):
+            cpc = after.get("cost_per_credit")
+            ct = after.get("credits_total")
+            if (not cpc or cpc == 0) and (not ct or ct == 0):
+                warning = "Achtung: cost_per_credit und credits_total sind leer/0 - Budget wird nicht getrackt. Bitte 'Unbegrenzt' aktivieren oder gueltige Werte eintragen."
+
+        logger.info(f"Budget fuer Lizenz {license_id} aktualisiert: {data}")
+        return {"ok": True, "warning": warning}
     finally:
         await db.close()
diff --git a/src/routers/users.py b/src/routers/users.py
index 455e886..6dab904 100644
--- a/src/routers/users.py
+++ b/src/routers/users.py
@@ -2,10 +2,11 @@
 import secrets
 import string
 from datetime import datetime, timedelta, timezone
-from fastapi import APIRouter, Depends, HTTPException, status
+from fastapi import APIRouter, Depends, HTTPException, status, Request
 from models import UserCreate, UserResponse
 from auth import get_current_admin
 from database import db_dependency
+from audit import log_action, get_client_ip, row_to_dict
 from config import MAGIC_LINK_BASE_URL, MAGIC_LINK_EXPIRE_MINUTES
 import aiosqlite
 
@@ -31,6 +32,7 @@ async def list_users(
 @router.post("", response_model=UserResponse, status_code=status.HTTP_201_CREATED)
 async def create_user(
     data: UserCreate,
+    request: Request,
     org_id: int = None,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
@@ -40,13 +42,11 @@ async def create_user(
 
     email = data.email.lower().strip()
 
-    # Org pruefen
     cursor = await db.execute("SELECT id, name FROM organizations WHERE id = ?", (org_id,))
     org = await cursor.fetchone()
     if not org:
         raise HTTPException(status_code=404, detail="Organisation nicht gefunden")
 
-    # Nutzer-Limit pruefen
     cursor = await db.execute(
         "SELECT max_users FROM licenses WHERE organization_id = ? AND status = 'active' ORDER BY created_at DESC LIMIT 1",
         (org_id,),
@@ -61,7 +61,6 @@ async def create_user(
         if current >= lic["max_users"]:
             raise HTTPException(status_code=400, detail=f"Nutzer-Limit erreicht ({current}/{lic['max_users']})")
 
-    # E-Mail-Duplikat
     cursor = await db.execute("SELECT id FROM users WHERE LOWER(email) = ?", (email,))
     if await cursor.fetchone():
         raise HTTPException(status_code=400, detail="E-Mail bereits vergeben")
@@ -75,7 +74,6 @@ async def create_user(
     )
     user_id = cursor.lastrowid
 
-    # Magic Link fuer Einladung erstellen
     token = secrets.token_urlsafe(48)
     code = ''.join(secrets.choice(string.digits) for _ in range(6))
     expires_at = (datetime.now(timezone.utc) + timedelta(hours=48)).isoformat()
@@ -87,7 +85,6 @@ async def create_user(
     )
     await db.commit()
 
-    # Einladungs-E-Mail senden
     try:
         from email_utils.sender import send_email
         from email_utils.templates import invite_email
@@ -95,47 +92,61 @@ async def create_user(
         subject, html = invite_email(username, org["name"], code, link)
         await send_email(email, subject, html)
     except Exception:
-        pass  # E-Mail-Fehler nicht fatal
+        pass
 
     cursor = await db.execute("SELECT * FROM users WHERE id = ?", (user_id,))
-    return dict(await cursor.fetchone())
+    new_user = dict(await cursor.fetchone())
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="create", resource_type="user", resource_id=user_id,
+        after={k: v for k, v in new_user.items() if k != "password_hash"},
+    )
+    return new_user
+
+
+async def _toggle_field(db, request, admin, user_id: int, field: str, value: int):
+    """Hilfsfunktion: ein Feld aktualisieren + Audit."""
+    before = await row_to_dict(db, "users", user_id)
+    if not before:
+        raise HTTPException(status_code=404, detail="Nutzer nicht gefunden")
+    await db.execute(f"UPDATE users SET {field} = ? WHERE id = ?", (value, user_id))
+    await db.commit()
+    after = await row_to_dict(db, "users", user_id)
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="update", resource_type="user", resource_id=user_id,
+        before={field: before.get(field)},
+        after={field: after.get(field)},
+    )
+    return after
 
 
 @router.put("/{user_id}/deactivate")
 async def deactivate_user(
     user_id: int,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
-    cursor = await db.execute("SELECT id FROM users WHERE id = ?", (user_id,))
-    if not await cursor.fetchone():
-        raise HTTPException(status_code=404, detail="Nutzer nicht gefunden")
-
-    await db.execute("UPDATE users SET is_active = 0 WHERE id = ?", (user_id,))
-    await db.commit()
+    await _toggle_field(db, request, admin, user_id, "is_active", 0)
     return {"ok": True}
 
 
 @router.put("/{user_id}/activate")
 async def activate_user(
     user_id: int,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
-    cursor = await db.execute("SELECT id FROM users WHERE id = ?", (user_id,))
-    if not await cursor.fetchone():
-        raise HTTPException(status_code=404, detail="Nutzer nicht gefunden")
-
-    await db.execute("UPDATE users SET is_active = 1 WHERE id = ?", (user_id,))
-    await db.commit()
+    await _toggle_field(db, request, admin, user_id, "is_active", 1)
     return {"ok": True}
 
 
-
-
 @router.put("/{user_id}/globe-access")
 async def toggle_globe_access(
     user_id: int,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
@@ -143,48 +154,15 @@ async def toggle_globe_access(
     row = await cursor.fetchone()
     if not row:
         raise HTTPException(status_code=404, detail="Nutzer nicht gefunden")
-
     new_val = 0 if row[1] else 1
-    await db.execute("UPDATE users SET globe_access = ? WHERE id = ?", (new_val, user_id))
-    await db.commit()
+    await _toggle_field(db, request, admin, user_id, "globe_access", new_val)
     return {"ok": True, "globe_access": bool(new_val)}
 
-@router.put("/{user_id}/role")
-async def change_role(
-    user_id: int,
-    role: str = "member",
-    admin: dict = Depends(get_current_admin),
-    db: aiosqlite.Connection = Depends(db_dependency),
-):
-    if role not in ("org_admin", "member"):
-        raise HTTPException(status_code=400, detail="Ungueltige Rolle")
-
-    cursor = await db.execute("SELECT id FROM users WHERE id = ?", (user_id,))
-    if not await cursor.fetchone():
-        raise HTTPException(status_code=404, detail="Nutzer nicht gefunden")
-
-    await db.execute("UPDATE users SET role = ? WHERE id = ?", (role, user_id))
-    await db.commit()
-    return {"ok": True}
-
-
-@router.delete("/{user_id}", status_code=status.HTTP_204_NO_CONTENT)
-async def delete_user(
-    user_id: int,
-    admin: dict = Depends(get_current_admin),
-    db: aiosqlite.Connection = Depends(db_dependency),
-):
-    cursor = await db.execute("SELECT id FROM users WHERE id = ?", (user_id,))
-    if not await cursor.fetchone():
-        raise HTTPException(status_code=404, detail="Nutzer nicht gefunden")
-
-    await db.execute("DELETE FROM users WHERE id = ?", (user_id,))
-    await db.commit()
-
 
 @router.put("/{user_id}/network-access")
 async def toggle_network_access(
     user_id: int,
+    request: Request,
     admin: dict = Depends(get_current_admin),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
@@ -192,8 +170,39 @@ async def toggle_network_access(
     row = await cursor.fetchone()
     if not row:
         raise HTTPException(status_code=404, detail="Nutzer nicht gefunden")
-
     new_val = 0 if row[1] else 1
-    await db.execute("UPDATE users SET network_access = ? WHERE id = ?", (new_val, user_id))
-    await db.commit()
+    await _toggle_field(db, request, admin, user_id, "network_access", new_val)
     return {"ok": True, "network_access": bool(new_val)}
+
+
+@router.put("/{user_id}/role")
+async def change_role(
+    user_id: int,
+    request: Request,
+    role: str = "member",
+    admin: dict = Depends(get_current_admin),
+    db: aiosqlite.Connection = Depends(db_dependency),
+):
+    if role not in ("org_admin", "member"):
+        raise HTTPException(status_code=400, detail="Ungueltige Rolle")
+    await _toggle_field(db, request, admin, user_id, "role", role)
+    return {"ok": True}
+
+
+@router.delete("/{user_id}", status_code=status.HTTP_204_NO_CONTENT)
+async def delete_user(
+    user_id: int,
+    request: Request,
+    admin: dict = Depends(get_current_admin),
+    db: aiosqlite.Connection = Depends(db_dependency),
+):
+    before = await row_to_dict(db, "users", user_id)
+    if not before:
+        raise HTTPException(status_code=404, detail="Nutzer nicht gefunden")
+    await db.execute("DELETE FROM users WHERE id = ?", (user_id,))
+    await db.commit()
+    await log_action(
+        db, admin, get_client_ip(request),
+        action="delete", resource_type="user", resource_id=user_id,
+        before={k: v for k, v in before.items() if k != "password_hash"},
+    )
diff --git a/src/static/css/style.css b/src/static/css/style.css
index a7c54e3..989918b 100644
--- a/src/static/css/style.css
+++ b/src/static/css/style.css
@@ -777,3 +777,16 @@ tr:hover td {
 .token-budget-bar.warning { background: #e67e22; }
 .token-budget-bar.critical { background: #e74c3c; }
 @media (max-width: 768px) { .token-stats-row { grid-template-columns: repeat(2, 1fr); } }
+
+/* === Audit-Log === */
+.audit-row { cursor: pointer; }
+.audit-row:hover { background: var(--bg-hover, rgba(255,255,255,0.03)); }
+.audit-detail-row td { background: var(--bg-tertiary, #0f172a); padding: 12px 16px; }
+.audit-diff { width: 100%; border-collapse: collapse; font-size: 12px; }
+.audit-diff th, .audit-diff td { padding: 4px 8px; border-bottom: 1px solid var(--border); text-align: left; vertical-align: top; }
+.audit-diff th { font-weight: 600; color: var(--text-secondary); }
+.audit-diff .diff-key { font-weight: 600; color: var(--text-secondary); width: 180px; word-break: break-word; }
+.audit-diff .diff-old { color: #e74c3c; word-break: break-word; }
+.audit-diff .diff-new { color: #2ecc71; word-break: break-word; }
+.token-budget-bar.over-limit { background: repeating-linear-gradient(45deg, #c0392b, #c0392b 6px, #962d22 6px, #962d22 12px); }
+input[type="date"].filter-select { padding: 6px 10px; }
diff --git a/src/static/dashboard.html b/src/static/dashboard.html
index 228f91e..47e4317 100644
--- a/src/static/dashboard.html
+++ b/src/static/dashboard.html
@@ -31,6 +31,7 @@
       <button class="nav-tab" data-section="orgs">Organisationen</button>
       <button class="nav-tab" data-section="licenses">Lizenzen</button>
       <button class="nav-tab" data-section="sources">Quellen</button>
+      <button class="nav-tab" data-section="audit">Audit-Log</button>
     </nav>
 
     <!-- Dashboard Section -->
@@ -224,6 +225,12 @@
             <div class="card" style="margin-top:12px;">
               <div class="card-body">
                 <form id="tokenBudgetForm" style="display:grid; grid-template-columns:1fr 1fr; gap:12px;">
+                  <div style="grid-column:1/-1; padding:8px 12px; background:var(--bg-tertiary,#0f172a); border-radius:6px; border:1px solid var(--border);">
+                    <label style="display:flex; align-items:center; gap:8px; cursor:pointer; margin:0;">
+                      <input type="checkbox" id="editUnlimitedBudget" onchange="onUnlimitedToggle()">
+                      <span><strong>Unbegrenztes Budget</strong> &mdash; Verbrauch wird trotzdem getrackt, aber kein Limit/Hard-Stop</span>
+                    </label>
+                  </div>
                   <div class="form-group">
                     <label for="editCreditsTotal">Credits-Kontingent</label>
                     <input type="number" id="editCreditsTotal" placeholder="z.B. 600000">
@@ -392,6 +399,48 @@
         </div>
       </div>
     </div>
+
+    <!-- Audit-Log Section -->
+    <div class="section" id="sec-audit">
+      <div class="action-bar" style="flex-wrap:wrap;gap:8px;">
+        <div style="display:flex;align-items:center;gap:8px;flex-wrap:wrap;">
+          <select class="filter-select" id="auditFilterAction">
+            <option value="">Alle Aktionen</option>
+          </select>
+          <select class="filter-select" id="auditFilterResource">
+            <option value="">Alle Ressourcen</option>
+          </select>
+          <select class="filter-select" id="auditFilterAdmin">
+            <option value="">Alle Admins</option>
+          </select>
+          <input type="date" class="filter-select" id="auditFilterFrom" title="Von (Datum)">
+          <input type="date" class="filter-select" id="auditFilterTo" title="Bis (Datum)">
+          <button class="btn btn-secondary btn-small" id="auditFilterReset">Filter zuruecksetzen</button>
+          <span class="text-secondary" id="auditCount"></span>
+        </div>
+        <div style="display:flex;align-items:center;gap:8px;">
+          <button class="btn btn-secondary btn-small" id="auditPrevBtn" disabled>&larr; Zurueck</button>
+          <button class="btn btn-secondary btn-small" id="auditNextBtn" disabled>Weiter &rarr;</button>
+        </div>
+      </div>
+      <div class="card">
+        <div class="table-wrap">
+          <table>
+            <thead>
+              <tr>
+                <th style="width:170px;">Zeitpunkt</th>
+                <th style="width:120px;">Admin</th>
+                <th style="width:140px;">IP</th>
+                <th style="width:140px;">Aktion</th>
+                <th>Ressource</th>
+                <th style="width:50px;"></th>
+              </tr>
+            </thead>
+            <tbody id="auditTable"><tr><td colspan="6" class="text-muted">Lade...</td></tr></tbody>
+          </table>
+        </div>
+      </div>
+    </div>
   </main>
 
   <!-- Modal: New Organization -->
@@ -478,6 +527,12 @@
             <div class="text-muted mt-8" style="font-size: 12px;">Trial: Standard 14 Tage, Jahreslizenz: Standard 365 Tage</div>
           </div>
 
+          <div class="form-group" style="background:var(--bg-tertiary,#0f172a); padding:8px 12px; border-radius:6px; border:1px solid var(--border);">
+            <label style="display:flex;align-items:center;gap:8px;cursor:pointer;margin:0;">
+              <input type="checkbox" id="newLicUnlimited" onchange="onNewLicUnlimitedToggle()">
+              <span><strong>Unbegrenztes Budget</strong> &mdash; getrackt, aber kein Hard-Stop</span>
+            </label>
+          </div>
           <div class="form-group">
             <label for="newLicCreditsTotal">Credits-Kontingent</label>
             <input type="number" id="newLicCreditsTotal" placeholder="z.B. 600000">
@@ -626,5 +681,6 @@
   <script src="/static/js/app.js"></script>
   <script src="/static/js/sources.js"></script>
   <script src="/static/js/source-health.js"></script>
+  <script src="/static/js/audit.js"></script>
 </body>
 </html>
diff --git a/src/static/index.html b/src/static/index.html
index 6bc2002..90db2a6 100644
--- a/src/static/index.html
+++ b/src/static/index.html
@@ -52,6 +52,11 @@
           }),
         });
 
+        if (res.status === 429) {
+          const data = await res.json().catch(() => ({}));
+          throw new Error(data.detail || 'Zu viele Fehlversuche. Bitte 15 Minuten warten.');
+        }
+
         if (!res.ok) {
           const data = await res.json();
           throw new Error(data.detail || 'Anmeldung fehlgeschlagen');
diff --git a/src/static/js/app.js b/src/static/js/app.js
index dd79e03..95481b9 100644
--- a/src/static/js/app.js
+++ b/src/static/js/app.js
@@ -64,6 +64,7 @@ function setupNavTabs() {
       document.getElementById(`sec-${section}`).classList.add("active");
 
       if (section === "licenses") loadExpiringLicenses();
+      if (section === "audit" && typeof loadAudit === "function") loadAudit();
     });
   });
 }
@@ -489,12 +490,16 @@ function setupForms() {
     if (licType !== "permanent") {
       body.duration_days = parseInt(document.getElementById("newLicDuration").value);
     }
-    const creditsTotal = document.getElementById('newLicCreditsTotal');
-    const costPerCredit = document.getElementById('newLicCostPerCredit');
-    const budgetUsd = document.getElementById('newLicBudgetUsd');
-    if (creditsTotal && creditsTotal.value) body.credits_total = parseInt(creditsTotal.value);
-    if (costPerCredit && costPerCredit.value) body.cost_per_credit = parseFloat(costPerCredit.value);
-    if (budgetUsd && budgetUsd.value) body.token_budget_usd = parseFloat(budgetUsd.value);
+    const unlimitedEl = document.getElementById('newLicUnlimited');
+    body.unlimited_budget = !!(unlimitedEl && unlimitedEl.checked);
+    if (!body.unlimited_budget) {
+      const creditsTotal = document.getElementById('newLicCreditsTotal');
+      const costPerCredit = document.getElementById('newLicCostPerCredit');
+      const budgetUsd = document.getElementById('newLicBudgetUsd');
+      if (creditsTotal && creditsTotal.value) body.credits_total = parseInt(creditsTotal.value);
+      if (costPerCredit && costPerCredit.value) body.cost_per_credit = parseFloat(costPerCredit.value);
+      if (budgetUsd && budgetUsd.value) body.token_budget_usd = parseFloat(budgetUsd.value);
+    }
     try {
       await API.post("/api/licenses", body);
       closeModal("modalNewLicense");
@@ -599,11 +604,17 @@ async function loadOrgTokenUsage(orgId) {
 
     const budget = current.budget || {};
     const usage = current.usage || {};
+    const unlimited = !!budget.unlimited_budget;
 
     const el = (id, val) => { const e = document.getElementById(id); if (e) e.textContent = val; };
     el('tokenCreditsUsed', budget.credits_used != null ? Math.round(budget.credits_used).toLocaleString('de-DE') : '-');
-    el('tokenCreditsRemaining', budget.credits_remaining != null ? budget.credits_remaining.toLocaleString('de-DE') : '-');
-    el('tokenBudgetUsd', budget.token_budget_usd != null ? '$' + Number(budget.token_budget_usd).toFixed(2) : '-');
+    if (unlimited) {
+      el('tokenCreditsRemaining', '∞ Unbegrenzt');
+      el('tokenBudgetUsd', '—');
+    } else {
+      el('tokenCreditsRemaining', budget.credits_remaining != null ? budget.credits_remaining.toLocaleString('de-DE') : '-');
+      el('tokenBudgetUsd', budget.token_budget_usd != null ? '$' + Number(budget.token_budget_usd).toFixed(2) : '-');
+    }
     el('tokenCostUsd', usage.total_cost_usd != null ? '$' + Number(usage.total_cost_usd).toFixed(2) : '-');
 
     // Source-Split anzeigen
@@ -616,14 +627,29 @@ async function loadOrgTokenUsage(orgId) {
 
     const bar = document.getElementById('tokenBudgetBar');
     const percentEl = document.getElementById('tokenBudgetPercent');
-    const percent = budget.credits_percent_used || 0;
-    if (bar) {
-      bar.style.width = Math.min(100, percent) + '%';
-      bar.classList.remove('warning', 'critical');
-      if (percent > 80) bar.classList.add('critical');
-      else if (percent > 50) bar.classList.add('warning');
+    const barWrap = bar ? bar.parentElement : null;
+    if (unlimited) {
+      if (bar) bar.style.width = '0%';
+      if (percentEl) percentEl.textContent = 'Unbegrenzt';
+      if (barWrap) barWrap.style.opacity = '0.4';
+    } else {
+      const percent = budget.credits_percent_used || 0;
+      if (bar) {
+        bar.style.width = Math.min(100, percent) + '%';
+        bar.classList.remove('warning', 'critical', 'over-limit');
+        if (percent > 100) bar.classList.add('over-limit');
+        else if (percent > 80) bar.classList.add('critical');
+        else if (percent > 50) bar.classList.add('warning');
+      }
+      if (percentEl) {
+        percentEl.textContent = percent > 100
+          ? ('UEBER LIMIT (' + percent.toFixed(1) + '%)')
+          : (percent.toFixed(1) + '%');
+        percentEl.style.color = percent > 100 ? 'var(--danger-text, #991b1b)' : '';
+        percentEl.style.fontWeight = percent > 100 ? '700' : '';
+      }
+      if (barWrap) barWrap.style.opacity = '1';
     }
-    if (percentEl) percentEl.textContent = percent.toFixed(1) + '%';
 
     fillBudgetForm(budget);
 
@@ -655,6 +681,37 @@ function fillBudgetForm(budget) {
   el('editCostPerCredit', budget.cost_per_credit);
   el('editBudgetUsd', budget.token_budget_usd);
   el('editCreditsUsed', budget.credits_used ? Math.round(budget.credits_used) : 0);
+  const cb = document.getElementById('editUnlimitedBudget');
+  if (cb) {
+    cb.checked = !!budget.unlimited_budget;
+    onUnlimitedToggle();
+  }
+}
+
+// Unlimited-Toggle: Felder ausgrauen wenn aktiv
+function onUnlimitedToggle() {
+  const cb = document.getElementById('editUnlimitedBudget');
+  const isUnlimited = cb && cb.checked;
+  ['editCreditsTotal','editCostPerCredit','editBudgetUsd'].forEach(function(id) {
+    const e = document.getElementById(id);
+    if (e) {
+      e.disabled = isUnlimited;
+      e.style.opacity = isUnlimited ? '0.4' : '1';
+    }
+  });
+}
+
+// Unlimited-Toggle im Lizenz-Modal
+function onNewLicUnlimitedToggle() {
+  const cb = document.getElementById('newLicUnlimited');
+  const isUnlimited = cb && cb.checked;
+  ['newLicCreditsTotal','newLicCostPerCredit','newLicBudgetUsd'].forEach(function(id) {
+    const e = document.getElementById(id);
+    if (e) {
+      e.disabled = isUnlimited;
+      e.style.opacity = isUnlimited ? '0.4' : '1';
+    }
+  });
 }
 
 async function loadDashboardTokenStats() {
@@ -701,19 +758,34 @@ document.addEventListener('DOMContentLoaded', function() {
         }
 
         var body = {};
+        var unlimitedCb = document.getElementById('editUnlimitedBudget');
+        var isUnlimited = !!(unlimitedCb && unlimitedCb.checked);
+        body.unlimited_budget = isUnlimited;
+
         var creditsTotal = document.getElementById('editCreditsTotal');
         var costPerCredit = document.getElementById('editCostPerCredit');
         var budgetUsd = document.getElementById('editBudgetUsd');
         var creditsUsed = document.getElementById('editCreditsUsed');
 
-        if (creditsTotal && creditsTotal.value) body.credits_total = parseInt(creditsTotal.value);
-        if (costPerCredit && costPerCredit.value) body.cost_per_credit = parseFloat(costPerCredit.value);
-        if (budgetUsd && budgetUsd.value) body.token_budget_usd = parseFloat(budgetUsd.value);
+        if (!isUnlimited) {
+          if (creditsTotal && creditsTotal.value) body.credits_total = parseInt(creditsTotal.value);
+          if (costPerCredit && costPerCredit.value) body.cost_per_credit = parseFloat(costPerCredit.value);
+          if (budgetUsd && budgetUsd.value) body.token_budget_usd = parseFloat(budgetUsd.value);
+        }
+        // credits_used immer mitsenden (auch im Unlimited-Modus, fuer Korrekturen)
         if (creditsUsed && creditsUsed.value !== '') body.credits_used = parseFloat(creditsUsed.value);
 
-        await API.put('/api/token-usage/budget/' + activeLic.id, body);
-        if (msgEl) msgEl.textContent = 'Gespeichert!';
-        setTimeout(function() { if (msgEl) msgEl.textContent = ''; }, 3000);
+        var result = await API.put('/api/token-usage/budget/' + activeLic.id, body);
+        if (msgEl) {
+          if (result && result.warning) {
+            msgEl.textContent = result.warning;
+            msgEl.style.color = 'var(--danger-text, #991b1b)';
+          } else {
+            msgEl.textContent = 'Gespeichert!';
+            msgEl.style.color = '';
+          }
+        }
+        setTimeout(function() { if (msgEl) { msgEl.textContent = ''; msgEl.style.color = ''; } }, 5000);
 
         // Daten neu laden
         loadOrgTokenUsage(currentOrgId);
diff --git a/src/static/js/audit.js b/src/static/js/audit.js
new file mode 100644
index 0000000..9d04580
--- /dev/null
+++ b/src/static/js/audit.js
@@ -0,0 +1,229 @@
+/* Audit-Log Tab */
+"use strict";
+
+let auditCache = { items: [], total: 0, offset: 0, limit: 200 };
+let auditDistinct = { actions: [], resource_types: [], admins: [] };
+let expandedRows = new Set();
+
+const ACTION_LABELS = {
+  create: "Erstellt",
+  update: "Geändert",
+  delete: "Gelöscht",
+  login_success: "Login erfolgreich",
+  login_failed: "Login fehlgeschlagen",
+  login_blocked: "Login blockiert",
+};
+
+const RESOURCE_LABELS = {
+  organization: "Organisation",
+  user: "Nutzer",
+  license: "Lizenz",
+  source: "Quelle",
+  admin: "Admin",
+  auth: "Auth",
+};
+
+const ACTION_BADGE_CLASS = {
+  create: "active",
+  update: "trial",
+  delete: "inactive",
+  login_success: "active",
+  login_failed: "inactive",
+  login_blocked: "inactive",
+};
+
+document.addEventListener("DOMContentLoaded", () => {
+  document.querySelectorAll('.nav-tab[data-section="audit"]').forEach((tab) => {
+    tab.addEventListener("click", () => loadAudit());
+  });
+
+  // Filter-Inputs verdrahten
+  ["auditFilterAction", "auditFilterResource", "auditFilterAdmin",
+   "auditFilterFrom", "auditFilterTo"].forEach((id) => {
+    const el = document.getElementById(id);
+    if (el) el.addEventListener("change", () => { auditCache.offset = 0; loadAudit(); });
+  });
+
+  const reset = document.getElementById("auditFilterReset");
+  if (reset) reset.addEventListener("click", () => {
+    ["auditFilterAction", "auditFilterResource", "auditFilterAdmin",
+     "auditFilterFrom", "auditFilterTo"].forEach((id) => {
+      const el = document.getElementById(id);
+      if (el) el.value = "";
+    });
+    auditCache.offset = 0;
+    loadAudit();
+  });
+
+  const prev = document.getElementById("auditPrevBtn");
+  const next = document.getElementById("auditNextBtn");
+  if (prev) prev.addEventListener("click", () => {
+    auditCache.offset = Math.max(0, auditCache.offset - auditCache.limit);
+    loadAudit();
+  });
+  if (next) next.addEventListener("click", () => {
+    if (auditCache.offset + auditCache.limit < auditCache.total) {
+      auditCache.offset += auditCache.limit;
+      loadAudit();
+    }
+  });
+});
+
+async function loadAuditDistinct() {
+  try {
+    auditDistinct = await API.get("/api/audit-log/distinct");
+
+    const actSel = document.getElementById("auditFilterAction");
+    if (actSel && actSel.options.length <= 1) {
+      auditDistinct.actions.forEach((a) => {
+        const opt = document.createElement("option");
+        opt.value = a;
+        opt.textContent = ACTION_LABELS[a] || a;
+        actSel.appendChild(opt);
+      });
+    }
+
+    const resSel = document.getElementById("auditFilterResource");
+    if (resSel && resSel.options.length <= 1) {
+      auditDistinct.resource_types.forEach((r) => {
+        const opt = document.createElement("option");
+        opt.value = r;
+        opt.textContent = RESOURCE_LABELS[r] || r;
+        resSel.appendChild(opt);
+      });
+    }
+
+    const admSel = document.getElementById("auditFilterAdmin");
+    if (admSel && admSel.options.length <= 1) {
+      auditDistinct.admins.forEach((a) => {
+        const opt = document.createElement("option");
+        opt.value = a.id;
+        opt.textContent = a.username;
+        admSel.appendChild(opt);
+      });
+    }
+  } catch (err) {
+    console.error("Audit-Filter laden fehlgeschlagen:", err);
+  }
+}
+
+async function loadAudit() {
+  await loadAuditDistinct();
+  const params = new URLSearchParams();
+  const action = document.getElementById("auditFilterAction")?.value;
+  const resource = document.getElementById("auditFilterResource")?.value;
+  const adminId = document.getElementById("auditFilterAdmin")?.value;
+  const from = document.getElementById("auditFilterFrom")?.value;
+  const to = document.getElementById("auditFilterTo")?.value;
+
+  if (action) params.append("action", action);
+  if (resource) params.append("resource_type", resource);
+  if (adminId) params.append("admin_id", adminId);
+  if (from) params.append("from_ts", from);
+  if (to) params.append("to_ts", to);
+  params.append("limit", auditCache.limit);
+  params.append("offset", auditCache.offset);
+
+  try {
+    const data = await API.get("/api/audit-log?" + params.toString());
+    auditCache.items = data.items;
+    auditCache.total = data.total;
+    auditCache.offset = data.offset;
+    renderAudit();
+  } catch (err) {
+    console.error("Audit-Log laden fehlgeschlagen:", err);
+  }
+}
+
+function formatAuditTs(ts) {
+  if (!ts) return "-";
+  try {
+    const d = new Date(ts.replace(" ", "T") + "Z");
+    return d.toLocaleString("de-DE", {
+      day: "2-digit", month: "2-digit", year: "numeric",
+      hour: "2-digit", minute: "2-digit", second: "2-digit",
+    });
+  } catch { return ts; }
+}
+
+function renderAuditDiff(before, after) {
+  if (before === null && after === null) return "—";
+  if (before === null && after !== null) {
+    // CREATE: voller Datensatz
+    const keys = Object.keys(after).filter(k => k !== "password_hash");
+    return '<table class="audit-diff"><tbody>' +
+      keys.map(k => `<tr><td class="diff-key">${esc(k)}</td><td>${esc(JSON.stringify(after[k]))}</td></tr>`).join("") +
+      '</tbody></table>';
+  }
+  if (before !== null && after === null) {
+    const keys = Object.keys(before).filter(k => k !== "password_hash");
+    return '<table class="audit-diff"><tbody>' +
+      keys.map(k => `<tr><td class="diff-key">${esc(k)}</td><td>${esc(JSON.stringify(before[k]))}</td></tr>`).join("") +
+      '</tbody></table>';
+  }
+  // UPDATE: Diff zeigen
+  const keys = new Set([...Object.keys(before || {}), ...Object.keys(after || {})]);
+  return '<table class="audit-diff"><thead><tr><th>Feld</th><th>vorher</th><th>nachher</th></tr></thead><tbody>' +
+    [...keys].map(k => {
+      const bv = (before || {})[k];
+      const av = (after || {})[k];
+      return `<tr><td class="diff-key">${esc(k)}</td><td class="diff-old">${esc(JSON.stringify(bv))}</td><td class="diff-new">${esc(JSON.stringify(av))}</td></tr>`;
+    }).join("") +
+    '</tbody></table>';
+}
+
+function renderAudit() {
+  const tbody = document.getElementById("auditTable");
+  const countEl = document.getElementById("auditCount");
+  if (!tbody) return;
+
+  if (auditCache.items.length === 0) {
+    tbody.innerHTML = '<tr><td colspan="6" class="text-muted">Keine Eintraege</td></tr>';
+    if (countEl) countEl.textContent = "0 Eintraege";
+    updateAuditPaginator();
+    return;
+  }
+
+  let html = "";
+  auditCache.items.forEach((it) => {
+    const actLabel = ACTION_LABELS[it.action] || it.action;
+    const resLabel = it.resource_type ? (RESOURCE_LABELS[it.resource_type] || it.resource_type) : "—";
+    const resId = it.resource_id ? "#" + it.resource_id : "";
+    const badgeCls = ACTION_BADGE_CLASS[it.action] || "trial";
+    const expanded = expandedRows.has(it.id);
+    const arrow = expanded ? "▼" : "▶";
+
+    html += `<tr class="audit-row" onclick="toggleAuditRow(${it.id})">
+      <td>${formatAuditTs(it.ts)}</td>
+      <td>${esc(it.admin_username || "—")}</td>
+      <td>${esc(it.ip || "—")}</td>
+      <td><span class="badge badge-${badgeCls}">${esc(actLabel)}</span></td>
+      <td>${esc(resLabel)} ${esc(resId)}</td>
+      <td style="text-align:right;color:var(--text-secondary)">${arrow}</td>
+    </tr>`;
+    if (expanded) {
+      html += `<tr class="audit-detail-row" id="audit-detail-${it.id}"><td colspan="6">${renderAuditDiff(it.before, it.after)}</td></tr>`;
+    }
+  });
+  tbody.innerHTML = html;
+
+  if (countEl) {
+    const start = auditCache.offset + 1;
+    const end = Math.min(auditCache.offset + auditCache.items.length, auditCache.total);
+    countEl.textContent = `${start}-${end} von ${auditCache.total}`;
+  }
+  updateAuditPaginator();
+}
+
+function toggleAuditRow(id) {
+  if (expandedRows.has(id)) expandedRows.delete(id);
+  else expandedRows.add(id);
+  renderAudit();
+}
+
+function updateAuditPaginator() {
+  const prev = document.getElementById("auditPrevBtn");
+  const next = document.getElementById("auditNextBtn");
+  if (prev) prev.disabled = auditCache.offset <= 0;
+  if (next) next.disabled = auditCache.offset + auditCache.limit >= auditCache.total;
+}