diff --git a/libraries/entities-renderer/src/EntityTreeRenderer.cpp b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
index 9f1185cfb9..01f87da334 100644
--- a/libraries/entities-renderer/src/EntityTreeRenderer.cpp
+++ b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
@@ -39,6 +39,7 @@ EntityTreeRenderer::EntityTreeRenderer(bool wantScripts, AbstractViewStateInterf
     OctreeRenderer(),
     _wantScripts(wantScripts),
     _entitiesScriptEngine(NULL),
+    _sandboxScriptEngine(NULL),
     _lastMouseEventValid(false),
     _viewState(viewState),
     _scriptingServices(scriptingServices),
@@ -58,7 +59,10 @@ EntityTreeRenderer::EntityTreeRenderer(bool wantScripts, AbstractViewStateInterf
 }
 
 EntityTreeRenderer::~EntityTreeRenderer() {
-    // do we need to delete the _entitiesScriptEngine?? or is it deleted by default
+    // NOTE: we don't need to delete _entitiesScriptEngine because it's owned by the application and gets cleaned up 
+    // automatically but we do need to delete our sandbox script engine.
+    delete _sandboxScriptEngine;
+    _sandboxScriptEngine = NULL;
 }
 
 void EntityTreeRenderer::clear() {
@@ -79,6 +83,8 @@ void EntityTreeRenderer::init() {
         _entitiesScriptEngine = new ScriptEngine(NO_SCRIPT, "Entities",
                                         _scriptingServices->getControllerScriptingInterface());
         _scriptingServices->registerScriptEngineWithApplicationServices(_entitiesScriptEngine);
+
+        _sandboxScriptEngine = new ScriptEngine(NO_SCRIPT, "Entities Sandbox", NULL);
     }
 
     // make sure our "last avatar position" is something other than our current position, so that on our
@@ -190,13 +196,15 @@ QScriptValue EntityTreeRenderer::loadEntityScript(EntityItem* entity) {
     if (isURL) {
         _entitiesScriptEngine->setParentURL(entity->getScript());
     }
-    QScriptValue entityScriptConstructor = _entitiesScriptEngine->evaluate(scriptContents);
+    QScriptValue entityScriptConstructor = _sandboxScriptEngine->evaluate(scriptContents);
     
     if (!entityScriptConstructor.isFunction()) {
         qDebug() << "EntityTreeRenderer::loadEntityScript() entity:" << entityID;
         qDebug() << "    NOT CONSTRUCTOR";
         qDebug() << "    SCRIPT:" << entityScript;
         return QScriptValue(); // invalid script
+    } else {
+        entityScriptConstructor = _entitiesScriptEngine->evaluate(scriptContents);
     }
 
     QScriptValue entityScriptObject = entityScriptConstructor.construct();
diff --git a/libraries/entities-renderer/src/EntityTreeRenderer.h b/libraries/entities-renderer/src/EntityTreeRenderer.h
index 92cc2c4dcc..73406bcc15 100644
--- a/libraries/entities-renderer/src/EntityTreeRenderer.h
+++ b/libraries/entities-renderer/src/EntityTreeRenderer.h
@@ -135,6 +135,7 @@ private:
     
     bool _wantScripts;
     ScriptEngine* _entitiesScriptEngine;
+    ScriptEngine* _sandboxScriptEngine;
 
     QScriptValue loadEntityScript(EntityItem* entity);
     QScriptValue loadEntityScript(const EntityItemID& entityItemID);