diff --git a/include/osgViewer/CompositeViewer b/include/osgViewer/CompositeViewer
index 95114db8b..f2fad849a 100644
--- a/include/osgViewer/CompositeViewer
+++ b/include/osgViewer/CompositeViewer
@@ -28,6 +28,7 @@ class OSGVIEWER_EXPORT CompositeViewer : public osg::Referenced
         virtual ~CompositeViewer();
 
         void addView(osgViewer::View* view);
+        void removeView(osgViewer::View* view);
         
         osgViewer::View* getView(unsigned i) { return _views[i].get(); }
         const osgViewer::View* getView(unsigned i) const { return _views[i].get(); }
@@ -144,6 +145,9 @@ class OSGVIEWER_EXPORT CompositeViewer : public osg::Referenced
         /** Get the graphics operation to call on realization of the viewers graphics windows.*/
         osg::Operation* getRealizeOperation() { return _realizeOperation.get(); }
 
+        /** Return true if viewer threads are running. */
+        bool areThreadsRunning() const { return _threadsRunning; }
+
         /** Stop any threads begin run by viewer.*/
         void stopThreading();
 
@@ -169,6 +173,8 @@ class OSGVIEWER_EXPORT CompositeViewer : public osg::Referenced
         bool _quitEventSetsDone;
         
         ThreadingModel _threadingModel;
+        bool           _threadsRunning;
+
         BarrierPosition _endBarrierPosition;
 
         osg::ref_ptr<osg::BarrierOperation> _startRenderingBarrier;
diff --git a/include/osgViewer/Viewer b/include/osgViewer/Viewer
index 91c1944a5..eaeb68bde 100644
--- a/include/osgViewer/Viewer
+++ b/include/osgViewer/Viewer
@@ -151,6 +151,9 @@ class OSGVIEWER_EXPORT Viewer : public osgViewer::View
         /** Set up the threading and processor affinity as per the viewers threading model.*/
         void setUpThreading();      
 
+        /** Return true if viewer threads are running. */
+        bool areThreadsRunning() const { return _threadsRunning; }
+
         /** Stop any threads begin run by viewer.*/
         void stopThreading();
 
diff --git a/src/osgViewer/CompositeViewer.cpp b/src/osgViewer/CompositeViewer.cpp
index edbc413e4..9f461ff93 100644
--- a/src/osgViewer/CompositeViewer.cpp
+++ b/src/osgViewer/CompositeViewer.cpp
@@ -81,9 +81,34 @@ CompositeViewer::~CompositeViewer()
 
 void CompositeViewer::addView(osgViewer::View* view)
 {
+    bool threadsWereRuinning = _threadsRunning;
+    if (threadsWereRuinning) stopThreading();
+
     _views.push_back(view);
     
     setUpRenderingSupport();
+    if (threadsWereRuinning) startThreading();
+}
+
+void CompositeViewer::removeView(osgViewer::View* view)
+{
+    for(Views::iterator itr = _views.begin();
+        itr != _views.end();
+        ++itr)
+    {
+        if (*itr == view)
+        {
+            bool threadsWereRuinning = _threadsRunning;
+            if (threadsWereRuinning) stopThreading();
+
+            _views.erase(itr);
+
+            setUpRenderingSupport();
+            if (threadsWereRuinning) startThreading();
+
+            return;
+        }
+    }
 }
 
 bool CompositeViewer::isRealized() const
@@ -188,6 +213,8 @@ void CompositeViewer::setEndBarrierPosition(BarrierPosition bp)
 
 void CompositeViewer::stopThreading()
 {
+    if (!_threadsRunning) return;
+
     if (_numThreadsOnBarrier==0) return;
 
     osg::notify(osg::INFO)<<"CompositeViewer::stopThreading() - stopping threading"<<std::endl;
@@ -278,6 +305,8 @@ unsigned int CompositeViewer::computeNumberOfThreadsIncludingMainRequired()
 
 void CompositeViewer::startThreading()
 {
+    if (_threadsRunning) return;
+
     unsigned int numThreadsIncludingMainThread = computeNumberOfThreadsIncludingMainRequired();
 
     // return if we don't need multiple threads.
@@ -394,6 +423,8 @@ void CompositeViewer::startThreading()
             // OpenThreads::Thread::YieldCurrentThread();
         }
     }
+
+    _threadsRunning = true;
 }
 
 void CompositeViewer::checkWindowStatus()