diff --git a/v2_adminpanel/app.py b/v2_adminpanel/app.py
index b1abb26..b2d5804 100644
--- a/v2_adminpanel/app.py
+++ b/v2_adminpanel/app.py
@@ -4469,26 +4469,60 @@ def allocate_resources_api():
 @login_required
 def check_resource_availability():
     """Prüft verfügbare Ressourcen"""
+    resource_type = request.args.get('type', '')
+    count = request.args.get('count', 10, type=int)
+    show_test = request.args.get('show_test', 'false').lower() == 'true'
+    
     conn = get_connection()
     cur = conn.cursor()
     
-    cur.execute("""
-        SELECT 
-            resource_type,
-            COUNT(*) as available
-        FROM resource_pools
-        WHERE status = 'available'
-        GROUP BY resource_type
-    """)
-    
-    availability = {}
-    for row in cur.fetchall():
-        availability[row[0]] = row[1]
-    
-    cur.close()
-    conn.close()
-    
-    return jsonify(availability)
+    if resource_type:
+        # Spezifische Ressourcen für einen Typ
+        cur.execute("""
+            SELECT id, resource_value
+            FROM resource_pools
+            WHERE status = 'available' 
+            AND resource_type = %s
+            AND is_test = %s
+            ORDER BY resource_value
+            LIMIT %s
+        """, (resource_type, show_test, count))
+        
+        resources = []
+        for row in cur.fetchall():
+            resources.append({
+                'id': row[0],
+                'value': row[1]
+            })
+        
+        cur.close()
+        conn.close()
+        
+        return jsonify({
+            'available': resources,
+            'type': resource_type,
+            'count': len(resources)
+        })
+    else:
+        # Zusammenfassung aller Typen
+        cur.execute("""
+            SELECT 
+                resource_type,
+                COUNT(*) as available
+            FROM resource_pools
+            WHERE status = 'available'
+            AND is_test = %s
+            GROUP BY resource_type
+        """, (show_test,))
+        
+        availability = {}
+        for row in cur.fetchall():
+            availability[row[0]] = row[1]
+        
+        cur.close()
+        conn.close()
+        
+        return jsonify(availability)
 
 @app.route('/api/global-search', methods=['GET'])
 @login_required
diff --git a/v2_adminpanel/templates/customers_licenses.html b/v2_adminpanel/templates/customers_licenses.html
index f7c8a6f..ff92edd 100644
--- a/v2_adminpanel/templates/customers_licenses.html
+++ b/v2_adminpanel/templates/customers_licenses.html
@@ -234,7 +234,7 @@
 
 <!-- Modal für Ressourcen-Verwaltung -->
 <div class="modal fade" id="resourceManagementModal" tabindex="-1">
-    <div class="modal-dialog modal-lg">
+    <div class="modal-dialog modal-xl">
         <div class="modal-content">
             <div class="modal-header">
                 <h5 class="modal-title">Ressourcen verwalten</h5>
@@ -244,8 +244,11 @@
                 <!-- Wird dynamisch gefüllt -->
             </div>
             <div class="modal-footer">
+                <div class="me-auto">
+                    <span class="text-muted" id="selectionCounter">0 Ressourcen ausgewählt</span>
+                </div>
                 <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Schließen</button>
-                <button type="button" class="btn btn-primary" onclick="saveResourceChanges()">
+                <button type="button" class="btn btn-primary" onclick="saveResourceChanges()" id="saveResourcesBtn">
                     <i class="bi bi-save"></i> Änderungen speichern
                 </button>
             </div>
@@ -310,6 +313,44 @@
 .btn-link {
     padding: 0 4px;
 }
+
+/* Multi-select improvements */
+select[multiple] {
+    scrollbar-width: thin;
+    scrollbar-color: #6c757d #f8f9fa;
+}
+
+select[multiple]::-webkit-scrollbar {
+    width: 8px;
+}
+
+select[multiple]::-webkit-scrollbar-track {
+    background: #f8f9fa;
+}
+
+select[multiple]::-webkit-scrollbar-thumb {
+    background-color: #6c757d;
+    border-radius: 4px;
+}
+
+select[multiple] option {
+    padding: 4px 8px;
+}
+
+select[multiple] option:checked {
+    background-color: #0d6efd;
+    color: white;
+}
+
+select[multiple] option:hover {
+    background-color: #e9ecef;
+    color: #212529;
+}
+
+/* Modal improvements */
+.modal-xl {
+    max-width: 1200px;
+}
 </style>
 {% endblock %}
 
@@ -672,6 +713,9 @@ function showResourceManagement(licenseId) {
     const license = currentLicenses[licenseId];
     if (!license) return;
     
+    // Speichere License-ID im Modal für späteren Zugriff
+    document.getElementById('resourceManagementModal').dataset.licenseId = licenseId;
+    
     // Lade aktuelle Ressourcen-Informationen
     fetch(`/api/license/${licenseId}/resources`)
         .then(response => response.json())
@@ -775,7 +819,62 @@ function showResourceManagement(licenseId) {
                 content += `
                     </div>
                     
-                    <div class="alert alert-warning">
+                    <hr class="my-4">
+                    
+                    <h6>Neue Ressourcen zuweisen</h6>
+                    <div class="alert alert-info">
+                        <i class="bi bi-info-circle"></i> Wählen Sie verfügbare Ressourcen aus, um sie dieser Lizenz zuzuweisen.
+                    </div>
+                    
+                    <div class="row g-3">
+                        <div class="col-md-4">
+                            <label class="form-label">🌐 Domains hinzufügen</label>
+                            <div class="text-muted small mb-2">Mehrfachauswahl mit Strg/Cmd + Klick</div>
+                            <select id="availableDomains" class="form-select" size="10" multiple>
+                                <option value="" disabled>Lade verfügbare Domains...</option>
+                            </select>
+                            <div class="mt-2">
+                                <button type="button" class="btn btn-sm btn-outline-secondary" onclick="selectAllInCategory('availableDomains')">
+                                    Alle auswählen
+                                </button>
+                                <button type="button" class="btn btn-sm btn-outline-secondary" onclick="deselectAllInCategory('availableDomains')">
+                                    Auswahl aufheben
+                                </button>
+                            </div>
+                        </div>
+                        <div class="col-md-4">
+                            <label class="form-label">📡 IPv4-Adressen hinzufügen</label>
+                            <div class="text-muted small mb-2">Mehrfachauswahl mit Strg/Cmd + Klick</div>
+                            <select id="availableIpv4s" class="form-select" size="10" multiple>
+                                <option value="" disabled>Lade verfügbare IPs...</option>
+                            </select>
+                            <div class="mt-2">
+                                <button type="button" class="btn btn-sm btn-outline-secondary" onclick="selectAllInCategory('availableIpv4s')">
+                                    Alle auswählen
+                                </button>
+                                <button type="button" class="btn btn-sm btn-outline-secondary" onclick="deselectAllInCategory('availableIpv4s')">
+                                    Auswahl aufheben
+                                </button>
+                            </div>
+                        </div>
+                        <div class="col-md-4">
+                            <label class="form-label">📱 Telefonnummern hinzufügen</label>
+                            <div class="text-muted small mb-2">Mehrfachauswahl mit Strg/Cmd + Klick</div>
+                            <select id="availablePhones" class="form-select" size="10" multiple>
+                                <option value="" disabled>Lade verfügbare Nummern...</option>
+                            </select>
+                            <div class="mt-2">
+                                <button type="button" class="btn btn-sm btn-outline-secondary" onclick="selectAllInCategory('availablePhones')">
+                                    Alle auswählen
+                                </button>
+                                <button type="button" class="btn btn-sm btn-outline-secondary" onclick="deselectAllInCategory('availablePhones')">
+                                    Auswahl aufheben
+                                </button>
+                            </div>
+                        </div>
+                    </div>
+                    
+                    <div class="alert alert-warning mt-3">
                         <i class="bi bi-exclamation-triangle"></i> 
                         Das Quarantäne-setzen einer Ressource entfernt sie von der Lizenz und markiert sie als problematisch.
                     </div>`;
@@ -783,6 +882,20 @@ function showResourceManagement(licenseId) {
                 document.getElementById('resourceManagementContent').innerHTML = content;
                 const modal = new bootstrap.Modal(document.getElementById('resourceManagementModal'));
                 modal.show();
+                
+                // Lade verfügbare Ressourcen
+                loadAvailableResources(licenseId);
+                
+                // Add event listeners for selection changes after resources are loaded
+                setTimeout(() => {
+                    ['availableDomains', 'availableIpv4s', 'availablePhones'].forEach(selectId => {
+                        const select = document.getElementById(selectId);
+                        if (select) {
+                            select.addEventListener('change', updateSelectionCounter);
+                        }
+                    });
+                    updateSelectionCounter();
+                }, 500);
             }
         })
         .catch(error => {
@@ -801,9 +914,187 @@ function quarantineResource(resourceId, resourceValue) {
     alert('Diese Funktion wird noch implementiert');
 }
 
-// Dummy-Funktion für Speichern (wird später implementiert)
+// Lade verfügbare Ressourcen
+function loadAvailableResources(licenseId) {
+    // Hole show_test Parameter aus der URL
+    const urlParams = new URLSearchParams(window.location.search);
+    const showTest = urlParams.get('show_test') === 'true';
+    
+    // Lade verfügbare Domains
+    fetch(`/api/resources/check-availability?type=domain&count=200&show_test=${showTest}`)
+        .then(response => response.json())
+        .then(data => {
+            const select = document.getElementById('availableDomains');
+            select.innerHTML = '';
+            if (data.available && data.available.length > 0) {
+                data.available.forEach(resource => {
+                    const option = document.createElement('option');
+                    option.value = resource.id;
+                    option.textContent = resource.value;
+                    select.appendChild(option);
+                });
+                // Zeige Anzahl verfügbarer Ressourcen
+                const label = select.parentElement.querySelector('.form-label');
+                label.innerHTML = `🌐 Domains hinzufügen (${data.available.length} verfügbar)`;
+            } else {
+                select.innerHTML = '<option value="" disabled>Keine verfügbaren Domains</option>';
+            }
+        });
+    
+    // Lade verfügbare IPv4s
+    fetch(`/api/resources/check-availability?type=ipv4&count=200&show_test=${showTest}`)
+        .then(response => response.json())
+        .then(data => {
+            const select = document.getElementById('availableIpv4s');
+            select.innerHTML = '';
+            if (data.available && data.available.length > 0) {
+                data.available.forEach(resource => {
+                    const option = document.createElement('option');
+                    option.value = resource.id;
+                    option.textContent = resource.value;
+                    select.appendChild(option);
+                });
+                // Zeige Anzahl verfügbarer Ressourcen
+                const label = select.parentElement.querySelector('.form-label');
+                label.innerHTML = `📡 IPv4-Adressen hinzufügen (${data.available.length} verfügbar)`;
+            } else {
+                select.innerHTML = '<option value="" disabled>Keine verfügbaren IPv4-Adressen</option>';
+            }
+        });
+    
+    // Lade verfügbare Telefonnummern
+    fetch(`/api/resources/check-availability?type=phone&count=200&show_test=${showTest}`)
+        .then(response => response.json())
+        .then(data => {
+            const select = document.getElementById('availablePhones');
+            select.innerHTML = '';
+            if (data.available && data.available.length > 0) {
+                data.available.forEach(resource => {
+                    const option = document.createElement('option');
+                    option.value = resource.id;
+                    option.textContent = resource.value;
+                    select.appendChild(option);
+                });
+                // Zeige Anzahl verfügbarer Ressourcen
+                const label = select.parentElement.querySelector('.form-label');
+                label.innerHTML = `📱 Telefonnummern hinzufügen (${data.available.length} verfügbar)`;
+            } else {
+                select.innerHTML = '<option value="" disabled>Keine verfügbaren Telefonnummern</option>';
+            }
+        });
+}
+
+// Alle Optionen in einer Kategorie auswählen
+function selectAllInCategory(selectId) {
+    const select = document.getElementById(selectId);
+    for (let i = 0; i < select.options.length; i++) {
+        if (!select.options[i].disabled) {
+            select.options[i].selected = true;
+        }
+    }
+    updateSelectionCounter();
+}
+
+// Auswahl in einer Kategorie aufheben
+function deselectAllInCategory(selectId) {
+    const select = document.getElementById(selectId);
+    for (let i = 0; i < select.options.length; i++) {
+        select.options[i].selected = false;
+    }
+    updateSelectionCounter();
+}
+
+// Update selection counter
+function updateSelectionCounter() {
+    const domainsCount = document.getElementById('availableDomains').selectedOptions.length;
+    const ipv4sCount = document.getElementById('availableIpv4s').selectedOptions.length;
+    const phonesCount = document.getElementById('availablePhones').selectedOptions.length;
+    const totalCount = domainsCount + ipv4sCount + phonesCount;
+    
+    const counter = document.getElementById('selectionCounter');
+    if (counter) {
+        counter.textContent = `${totalCount} Ressourcen ausgewählt`;
+        
+        // Update save button state
+        const saveBtn = document.getElementById('saveResourcesBtn');
+        if (saveBtn) {
+            saveBtn.disabled = totalCount === 0;
+            if (totalCount === 0) {
+                saveBtn.classList.add('disabled');
+            } else {
+                saveBtn.classList.remove('disabled');
+            }
+        }
+    }
+}
+
+// Speichere Ressourcen-Änderungen
 function saveResourceChanges() {
-    alert('Diese Funktion wird noch implementiert');
+    const modal = document.getElementById('resourceManagementModal');
+    const licenseId = modal.dataset.licenseId || currentLicenses[Object.keys(currentLicenses)[0]].id;
+    
+    // Sammle ausgewählte Ressourcen
+    const selectedDomains = Array.from(document.getElementById('availableDomains').selectedOptions).map(opt => opt.value);
+    const selectedIpv4s = Array.from(document.getElementById('availableIpv4s').selectedOptions).map(opt => opt.value);
+    const selectedPhones = Array.from(document.getElementById('availablePhones').selectedOptions).map(opt => opt.value);
+    
+    const allResources = [...selectedDomains, ...selectedIpv4s, ...selectedPhones];
+    
+    if (allResources.length === 0) {
+        alert('Bitte wählen Sie mindestens eine Ressource aus.');
+        return;
+    }
+    
+    // Disable save button and show loading state
+    const saveBtn = document.getElementById('saveResourcesBtn');
+    const originalBtnText = saveBtn.innerHTML;
+    saveBtn.disabled = true;
+    saveBtn.innerHTML = '<span class="spinner-border spinner-border-sm me-2" role="status"></span>Wird gespeichert...';
+    
+    // API-Call zum Zuweisen der Ressourcen
+    fetch('/api/resources/allocate', {
+        method: 'POST',
+        headers: {
+            'Content-Type': 'application/json',
+        },
+        body: JSON.stringify({
+            license_id: licenseId,
+            resource_ids: allResources
+        })
+    })
+    .then(response => response.json())
+    .then(data => {
+        if (data.success) {
+            // Show success message with details
+            const domainCount = selectedDomains.length;
+            const ipv4Count = selectedIpv4s.length;
+            const phoneCount = selectedPhones.length;
+            
+            let message = `✅ ${data.allocated} Ressourcen erfolgreich zugewiesen!\n\n`;
+            if (domainCount > 0) message += `🌐 ${domainCount} Domains\n`;
+            if (ipv4Count > 0) message += `📡 ${ipv4Count} IPv4-Adressen\n`;
+            if (phoneCount > 0) message += `📱 ${phoneCount} Telefonnummern`;
+            
+            alert(message);
+            
+            // Modal schließen und Ansicht aktualisieren
+            bootstrap.Modal.getInstance(modal).hide();
+            if (currentCustomerId) {
+                loadCustomerLicenses(currentCustomerId);
+            }
+        } else {
+            alert('❌ ' + (data.message || 'Fehler beim Zuweisen der Ressourcen'));
+        }
+    })
+    .catch(error => {
+        console.error('Error allocating resources:', error);
+        alert('❌ Fehler beim Zuweisen der Ressourcen');
+    })
+    .finally(() => {
+        // Restore button state
+        saveBtn.disabled = false;
+        saveBtn.innerHTML = originalBtnText;
+    });
 }
 
 // Geräte-Verwaltung anzeigen