diff --git a/frontend/src/components/BaseDialog.vue b/frontend/src/components/BaseDialog.vue
index 67539462..229552ea 100644
--- a/frontend/src/components/BaseDialog.vue
+++ b/frontend/src/components/BaseDialog.vue
@@ -5,6 +5,7 @@
     @click.self="handleOverlayClick"
   >
     <div 
+      ref="dialogContainer"
       :class="['dialog-container', sizeClass]"
       :style="dialogStyle"
       @mousedown="handleMouseDown"
@@ -17,9 +18,10 @@
       >
         <h3 class="dialog-title">{{ title }}</h3>
         <slot name="header-actions"></slot>
-        <div class="dialog-controls">
+        <div class="dialog-controls" @mousedown.stop>
           <button 
             v-if="minimizable" 
+            type="button"
             @click="$emit('minimize')" 
             class="control-btn minimize-btn" 
             :title="$t('baseDialog.minimize')"
@@ -28,6 +30,7 @@
           </button>
           <button 
             v-if="closable" 
+            type="button"
             @click="handleClose" 
             class="control-btn close-btn" 
             :title="$t('baseDialog.close')"
@@ -46,6 +49,13 @@
       <div v-if="$slots.footer" class="dialog-footer">
         <slot name="footer"></slot>
       </div>
+
+      <div
+        v-if="!isModal && resizable"
+        class="dialog-resize-handle"
+        :title="$t('baseDialog.resize')"
+        @mousedown.stop="startResize"
+      />
     </div>
   </div>
 </template>
@@ -116,6 +126,12 @@ export default {
       type: Boolean,
       default: true
     },
+
+    /** Nicht-modale Dialoge: Ecke zum Vergrößern/Verkleinern */
+    resizable: {
+      type: Boolean,
+      default: true
+    },
     
     // Schließen bei Overlay-Klick (nur bei modalen Dialogen)
     closeOnOverlay: {
@@ -129,7 +145,11 @@ export default {
       localPosition: { ...this.position },
       isDragging: false,
       dragStartX: 0,
-      dragStartY: 0
+      dragStartY: 0,
+      localWidth: null,
+      localHeight: null,
+      isResizing: false,
+      resizeStart: null,
     };
   },
   
@@ -158,6 +178,14 @@ export default {
       if (!this.isModal) {
         style.left = `${this.localPosition.x}px`;
         style.top = `${this.localPosition.y}px`;
+        if (this.localWidth != null) {
+          style.width = `${this.localWidth}px`;
+          style.maxWidth = 'none';
+        }
+        if (this.localHeight != null) {
+          style.height = `${this.localHeight}px`;
+          style.maxHeight = 'none';
+        }
       }
       
       return style;
@@ -188,7 +216,11 @@ export default {
     
     startDrag(event) {
       if (!this.isDraggable) return;
-      
+      if (event.button !== 0) return;
+      if (event.target.closest('button, a, input, select, textarea, [contenteditable="true"]')) {
+        return;
+      }
+
       this.isDragging = true;
       this.dragStartX = event.clientX - this.localPosition.x;
       this.dragStartY = event.clientY - this.localPosition.y;
@@ -201,9 +233,20 @@ export default {
     
     onDrag(event) {
       if (!this.isDragging) return;
-      
-      this.localPosition.x = event.clientX - this.dragStartX;
-      this.localPosition.y = event.clientY - this.dragStartY;
+
+      let nx = event.clientX - this.dragStartX;
+      let ny = event.clientY - this.dragStartY;
+      const el = this.$refs.dialogContainer;
+      if (el && typeof window !== 'undefined') {
+        const w = el.offsetWidth;
+        const h = el.offsetHeight;
+        const pad = 8;
+        nx = Math.min(Math.max(pad, nx), window.innerWidth - w - pad);
+        ny = Math.min(Math.max(pad, ny), window.innerHeight - h - pad);
+      }
+
+      this.localPosition.x = nx;
+      this.localPosition.y = ny;
       
       this.$emit('update:position', { ...this.localPosition });
     },
@@ -212,7 +255,48 @@ export default {
       this.isDragging = false;
       document.removeEventListener('mousemove', this.onDrag);
       document.removeEventListener('mouseup', this.stopDrag);
-    }
+    },
+
+    startResize(event) {
+      if (this.isModal || !this.resizable) return;
+      if (event.button !== 0) return;
+      const el = this.$refs.dialogContainer;
+      if (!el) return;
+      const rect = el.getBoundingClientRect();
+      this.isResizing = true;
+      this.resizeStart = {
+        mouseX: event.clientX,
+        mouseY: event.clientY,
+        width: rect.width,
+        height: rect.height,
+      };
+      document.addEventListener('mousemove', this.onResizeMove);
+      document.addEventListener('mouseup', this.stopResize);
+      event.preventDefault();
+    },
+
+    onResizeMove(event) {
+      if (!this.isResizing || !this.resizeStart || typeof window === 'undefined') return;
+      const dx = event.clientX - this.resizeStart.mouseX;
+      const dy = event.clientY - this.resizeStart.mouseY;
+      let w = this.resizeStart.width + dx;
+      let h = this.resizeStart.height + dy;
+      const minW = 260;
+      const minH = 160;
+      const maxW = window.innerWidth - this.localPosition.x - 8;
+      const maxH = window.innerHeight - this.localPosition.y - 8;
+      w = Math.min(Math.max(minW, w), maxW);
+      h = Math.min(Math.max(minH, h), maxH);
+      this.localWidth = w;
+      this.localHeight = h;
+    },
+
+    stopResize() {
+      this.isResizing = false;
+      this.resizeStart = null;
+      document.removeEventListener('mousemove', this.onResizeMove);
+      document.removeEventListener('mouseup', this.stopResize);
+    },
   },
   
   watch: {
@@ -228,6 +312,9 @@ export default {
     if (this.isDragging) {
       this.stopDrag();
     }
+    if (this.isResizing) {
+      this.stopResize();
+    }
   }
 };
 </script>
@@ -265,6 +352,7 @@ export default {
 
 /* Dialog Container */
 .dialog-container {
+  position: relative;
   background: white;
   border-radius: 8px;
   box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
@@ -283,6 +371,8 @@ export default {
 /* Non-Modal Dialog Container */
 .non-modal-dialog .dialog-container {
   position: absolute;
+  min-width: 260px;
+  min-height: 160px;
 }
 
 /* Größen */
@@ -321,7 +411,34 @@ export default {
 }
 
 .dialog-header.draggable {
-  cursor: move;
+  cursor: grab;
+}
+
+.dialog-header.draggable:active {
+  cursor: grabbing;
+}
+
+.dialog-resize-handle {
+  position: absolute;
+  right: 0;
+  bottom: 0;
+  width: 16px;
+  height: 16px;
+  cursor: nwse-resize;
+  background: linear-gradient(
+    135deg,
+    transparent 50%,
+    rgba(0, 0, 0, 0.12) 50%
+  );
+  border-bottom-right-radius: 8px;
+}
+
+.dialog-resize-handle:hover {
+  background: linear-gradient(
+    135deg,
+    transparent 45%,
+    rgba(47, 122, 95, 0.35) 45%
+  );
 }
 
 .dialog-title {
diff --git a/frontend/src/components/DialogManager.vue b/frontend/src/components/DialogManager.vue
index 3cc3bc18..e6edad35 100644
--- a/frontend/src/components/DialogManager.vue
+++ b/frontend/src/components/DialogManager.vue
@@ -21,11 +21,7 @@
       v-for="dialog in activeDialogs"
       :key="dialog.id"
       class="dialog-window"
-      :style="{
-        left: dialog.position.x + 'px',
-        top: dialog.position.y + 'px',
-        zIndex: dialog.zIndex
-      }"
+      :style="dialogWindowStyle(dialog)"
       @mousedown="bringToFront(dialog.id)"
     >
       <div class="dialog-header" @mousedown="startDrag(dialog.id, $event)">
@@ -39,14 +35,19 @@
             @action="handleHeaderAction"
           />
         </div>
-        <div class="dialog-controls">
-          <button @click="minimizeDialog(dialog.id)" class="control-btn minimize-btn" :title="$t('dialogManager.minimize')">−</button>
-          <button @click="closeDialog(dialog.id)" class="control-btn close-btn" :title="$t('dialogManager.close')">×</button>
+        <div class="dialog-controls" @mousedown.stop>
+          <button type="button" @click="minimizeDialog(dialog.id)" class="control-btn minimize-btn" :title="$t('dialogManager.minimize')">−</button>
+          <button type="button" @click="closeDialog(dialog.id)" class="control-btn close-btn" :title="$t('dialogManager.close')">×</button>
         </div>
       </div>
       <div class="dialog-content">
         <component :is="getDialogComponent(dialog.component)" v-bind="dialog.props" @close="() => closeDialog(dialog.id)" />
       </div>
+      <div
+        class="dialog-resize-handle"
+        :title="$t('baseDialog.resize')"
+        @mousedown.stop="startResize(dialog.id, $event)"
+      />
     </div>
   </div>
 </template>
@@ -69,6 +70,9 @@ const InternalTournamentStats = defineAsyncComponent(() =>
   import('./tournament/InternalTournamentStats.vue'),
 );
 
+const MIN_DIALOG_W = 280;
+const MIN_DIALOG_H = 200;
+
 export default {
   components: {
     MatchReportDialog,
@@ -84,11 +88,42 @@ export default {
     InternalTournamentStats,
   },
   name: 'DialogManager',
+  data() {
+    return {
+      dragSession: null,
+      resizeSession: null,
+    };
+  },
   computed: {
     ...mapGetters(['dialogs', 'minimizedDialogs', 'activeDialogs'])
   },
   methods: {
-    ...mapActions(['closeDialog', 'minimizeDialog', 'restoreDialog', 'bringDialogToFront']),
+    ...mapActions(['closeDialog', 'minimizeDialog', 'restoreDialog', 'bringDialogToFront', 'updateDialogBounds']),
+
+    dialogWindowStyle(dialog) {
+      const s = {
+        left: `${dialog.position.x}px`,
+        top: `${dialog.position.y}px`,
+        zIndex: dialog.zIndex,
+      };
+      if (dialog.width != null && Number.isFinite(Number(dialog.width))) {
+        s.width = `${Number(dialog.width)}px`;
+      }
+      if (dialog.height != null && Number.isFinite(Number(dialog.height))) {
+        s.height = `${Number(dialog.height)}px`;
+      }
+      return s;
+    },
+
+    approxDialogWidth(dialog) {
+      if (dialog.width != null && Number.isFinite(Number(dialog.width))) return Number(dialog.width);
+      return Math.round(window.innerWidth * 0.9);
+    },
+
+    approxDialogHeight(dialog) {
+      if (dialog.height != null && Number.isFinite(Number(dialog.height))) return Number(dialog.height);
+      return Math.round(window.innerHeight * 0.9);
+    },
     
     getDialogComponent(componentName) {
       const components = {
@@ -113,9 +148,91 @@ export default {
     },
     
     startDrag(dialogId, event) {
-      // Drag & Drop deaktiviert, da Dialog jetzt fest positioniert ist
-      // Dialog wird immer zentriert angezeigt
-      this.bringToFront(dialogId);
+      if (event.button !== 0) return;
+      if (event.target.closest('button, a, input, select, textarea, [contenteditable="true"]')) {
+        return;
+      }
+      const dialog = this.dialogs.find((d) => d.id === dialogId);
+      if (!dialog) return;
+      this.bringDialogToFront(dialogId);
+      this.dragSession = {
+        dialogId,
+        startX: event.clientX,
+        startY: event.clientY,
+        origX: dialog.position.x,
+        origY: dialog.position.y,
+      };
+      document.addEventListener('mousemove', this.onDragMove);
+      document.addEventListener('mouseup', this.onDragEnd);
+      event.preventDefault();
+    },
+
+    onDragMove(event) {
+      if (!this.dragSession) return;
+      const { dialogId, startX, startY, origX, origY } = this.dragSession;
+      const dialog = this.dialogs.find((d) => d.id === dialogId);
+      if (!dialog) return;
+      let nx = origX + event.clientX - startX;
+      let ny = origY + event.clientY - startY;
+      const w = this.approxDialogWidth(dialog);
+      const h = this.approxDialogHeight(dialog);
+      const pad = 8;
+      nx = Math.min(Math.max(pad, nx), window.innerWidth - w - pad);
+      ny = Math.min(Math.max(pad, ny), window.innerHeight - h - pad);
+      this.updateDialogBounds({ dialogId, position: { x: nx, y: ny } });
+    },
+
+    onDragEnd() {
+      this.dragSession = null;
+      document.removeEventListener('mousemove', this.onDragMove);
+      document.removeEventListener('mouseup', this.onDragEnd);
+    },
+
+    startResize(dialogId, event) {
+      if (event.button !== 0) return;
+      this.bringDialogToFront(dialogId);
+      const dialog = this.dialogs.find((d) => d.id === dialogId);
+      if (!dialog) return;
+      const el = event.currentTarget.closest('.dialog-window');
+      if (!el) return;
+      const rect = el.getBoundingClientRect();
+      this.resizeSession = {
+        dialogId,
+        startX: event.clientX,
+        startY: event.clientY,
+        origW: rect.width,
+        origH: rect.height,
+      };
+      document.addEventListener('mousemove', this.onResizeMove);
+      document.addEventListener('mouseup', this.onResizeEnd);
+      event.preventDefault();
+    },
+
+    onResizeMove(event) {
+      if (!this.resizeSession) return;
+      const { dialogId, startX, startY, origW, origH } = this.resizeSession;
+      const dialog = this.dialogs.find((d) => d.id === dialogId);
+      if (!dialog) return;
+      let w = origW + event.clientX - startX;
+      let h = origH + event.clientY - startY;
+      const maxW = window.innerWidth - dialog.position.x - 8;
+      const maxH = window.innerHeight - dialog.position.y - 8;
+      w = Math.min(Math.max(MIN_DIALOG_W, w), maxW);
+      h = Math.min(Math.max(MIN_DIALOG_H, h), maxH);
+      this.updateDialogBounds({ dialogId, width: w, height: h });
+      let nx = dialog.position.x;
+      let ny = dialog.position.y;
+      if (nx + w > window.innerWidth - 8) nx = Math.max(8, window.innerWidth - w - 8);
+      if (ny + h > window.innerHeight - 8) ny = Math.max(8, window.innerHeight - h - 8);
+      if (nx !== dialog.position.x || ny !== dialog.position.y) {
+        this.updateDialogBounds({ dialogId, position: { x: nx, y: ny } });
+      }
+    },
+
+    onResizeEnd() {
+      this.resizeSession = null;
+      document.removeEventListener('mousemove', this.onResizeMove);
+      document.removeEventListener('mouseup', this.onResizeEnd);
     },
     
     handleHeaderAction(action) {
@@ -187,8 +304,9 @@ export default {
   },
   
   beforeUnmount() {
-    // Event-Listener entfernen
     window.removeEventListener('message', this.handlePostMessage);
+    if (this.dragSession) this.onDragEnd();
+    if (this.resizeSession) this.onResizeEnd();
   }
 };
 </script>
@@ -206,8 +324,11 @@ export default {
 
 .dialog-window {
   position: absolute;
-  width: 90vw;
-  height: 90vh;
+  box-sizing: border-box;
+  min-width: 280px;
+  min-height: 200px;
+  width: min(90vw, calc(100vw - 32px));
+  height: min(90vh, calc(100vh - 32px));
   background: white;
   border-radius: 8px;
   box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
@@ -215,8 +336,6 @@ export default {
   display: flex;
   flex-direction: column;
   overflow: hidden;
-  left: 5vw !important;
-  top: 5vh !important;
 }
 
 .dialog-header {
@@ -226,8 +345,13 @@ export default {
   display: flex;
   justify-content: space-between;
   align-items: center;
-  cursor: move;
+  cursor: grab;
   user-select: none;
+  flex-shrink: 0;
+}
+
+.dialog-header:active {
+  cursor: grabbing;
 }
 
 .dialog-title {
@@ -276,6 +400,31 @@ export default {
   flex: 1;
   padding: 0;
   overflow-y: auto;
+  min-height: 0;
+}
+
+.dialog-resize-handle {
+  position: absolute;
+  right: 0;
+  bottom: 0;
+  width: 16px;
+  height: 16px;
+  cursor: nwse-resize;
+  background: linear-gradient(
+    135deg,
+    transparent 50%,
+    rgba(0, 0, 0, 0.1) 50%
+  );
+  border-bottom-right-radius: 8px;
+  z-index: 2;
+}
+
+.dialog-resize-handle:hover {
+  background: linear-gradient(
+    135deg,
+    transparent 45%,
+    rgba(47, 122, 95, 0.35) 45%
+  );
 }
 
 .minimized-dialogs {
@@ -321,10 +470,8 @@ export default {
 /* Responsive Design */
 @media (max-width: 768px) {
   .dialog-window {
-    width: 95vw;
-    height: 95vh;
-    left: 2.5vw !important;
-    top: 2.5vh !important;
+    max-width: calc(100vw - 16px);
+    max-height: calc(100vh - 16px);
   }
   
   .minimized-dialogs {
diff --git a/frontend/src/i18n/locales/de.json b/frontend/src/i18n/locales/de.json
index b1acb459..fb038b62 100644
--- a/frontend/src/i18n/locales/de.json
+++ b/frontend/src/i18n/locales/de.json
@@ -2078,7 +2078,8 @@
   },
   "baseDialog": {
     "minimize": "Minimieren",
-    "close": "Schließen"
+    "close": "Schließen",
+    "resize": "Größe ändern"
   },
   "dialogManager": {
     "noMinimizedDialogs": "Keine minimierten Dialoge",
diff --git a/frontend/src/store.js b/frontend/src/store.js
index 2ac71405..a65cc371 100644
--- a/frontend/src/store.js
+++ b/frontend/src/store.js
@@ -109,15 +109,39 @@ const store = createStore({
     // Dialog-Mutations
     openDialog(state, dialog) {
       const id = ++state.dialogCounter;
+      let position = { x: 48, y: 48 };
+      if (
+        dialog.position &&
+        Number.isFinite(dialog.position.x) &&
+        Number.isFinite(dialog.position.y)
+      ) {
+        position = { x: dialog.position.x, y: dialog.position.y };
+      } else if (typeof window !== 'undefined') {
+        position = {
+          x: Math.max(16, Math.round(window.innerWidth * 0.05)),
+          y: Math.max(16, Math.round(window.innerHeight * 0.05)),
+        };
+      }
       const newDialog = {
         id,
         ...dialog,
         isMinimized: false,
         zIndex: 1000 + state.dialogs.length,
-        position: { x: 0, y: 0 } // Position wird durch CSS festgelegt
+        position,
+        width: dialog.width != null ? dialog.width : null,
+        height: dialog.height != null ? dialog.height : null,
       };
       state.dialogs.push(newDialog);
     },
+    updateDialogBounds(state, { dialogId, position, width, height }) {
+      const d = state.dialogs.find((x) => x.id === dialogId);
+      if (!d) return;
+      if (position && Number.isFinite(position.x) && Number.isFinite(position.y)) {
+        d.position = { x: position.x, y: position.y };
+      }
+      if (width !== undefined) d.width = width;
+      if (height !== undefined) d.height = height;
+    },
     closeDialog(state, dialogId) {
       state.dialogs = state.dialogs.filter(dialog => dialog.id !== dialogId);
     },
@@ -219,7 +243,10 @@ const store = createStore({
     },
     bringDialogToFront({ commit }, dialogId) {
       commit('bringDialogToFront', dialogId);
-    }
+    },
+    updateDialogBounds({ commit }, payload) {
+      commit('updateDialogBounds', payload);
+    },
   },
   getters: {
     isAuthenticated: state => !!state.token,