--- a/api.visual/src/org/netbeans/api/visual/graph/layout/GraphLayout.java	
+++ a/api.visual/src/org/netbeans/api/visual/graph/layout/GraphLayout.java	
@@ -100,7 +100,7 @@ 
      */
     public final void removeGraphLayoutListener (GraphLayoutListener<N,E> listener) {
         synchronized (listeners) {
-            listeners.add (listener);
+            listeners.remove (listener);
         }
     }