diff --git a/assignment-client/src/AssignmentClient.cpp b/assignment-client/src/AssignmentClient.cpp
index 0d62b8dcc7..3bd38c4ae7 100644
--- a/assignment-client/src/AssignmentClient.cpp
+++ b/assignment-client/src/AssignmentClient.cpp
@@ -31,6 +31,7 @@
 #include <ShutdownEventListener.h>
 #include <SoundCache.h>
 #include <ResourceScriptingInterface.h>
+#include <ScriptEngines.h>
 
 #include "AssignmentFactory.h"
 #include "AssignmentActionFactory.h"
@@ -53,6 +54,7 @@ AssignmentClient::AssignmentClient(Assignment::Type requestAssignmentType, QStri
  
     auto scriptableAvatar = DependencyManager::set<ScriptableAvatar>();
     auto addressManager = DependencyManager::set<AddressManager>();
+    auto scriptEngines = DependencyManager::set<ScriptEngines>();
 
     // create a NodeList as an unassigned client, must be after addressManager
     auto nodeList = DependencyManager::set<NodeList>(NodeType::Unassigned, listenPort);
@@ -174,6 +176,8 @@ AssignmentClient::~AssignmentClient() {
 void AssignmentClient::aboutToQuit() {
     stopAssignmentClient();
 
+    DependencyManager::destroy<ScriptEngines>();
+
     // clear the log handler so that Qt doesn't call the destructor on LogHandler
     qInstallMessageHandler(0);
 }
diff --git a/interface/resources/qml/AddressBarDialog.qml b/interface/resources/qml/AddressBarDialog.qml
index 6c94f9d254..e8ebb5d5fb 100644
--- a/interface/resources/qml/AddressBarDialog.qml
+++ b/interface/resources/qml/AddressBarDialog.qml
@@ -32,9 +32,14 @@ DialogContainer {
     property int maximumY: parent ? parent.height - height : 0
 
 
+    Rectangle {
+        id: dragRegion
+        visible: dragMouseArea.containsMouse
+    } 
+
     AddressBarDialog {
         id: addressBarDialog
-
+        z: dragRegion.z + 1
         implicitWidth: backgroundImage.width
         implicitHeight: backgroundImage.height
 
@@ -48,11 +53,13 @@ DialogContainer {
             property int inputAreaStep: (height - inputAreaHeight) / 2
 
             MouseArea {
+                id: dragMouseArea
                 // Drag the icon
                 width: parent.height
                 height: parent.height
                 x: 0
                 y: 0
+                hoverEnabled: true
                 drag {
                     target: root
                     minimumX: -parent.inputAreaStep
@@ -61,6 +68,8 @@ DialogContainer {
                     maximumY: root.parent ? root.maximumY + parent.inputAreaStep : 0
                 }
             }
+            
+            
 
             MouseArea {
                 // Drag the input rectangle
diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index 2fdd778339..4f0b514827 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -103,6 +103,7 @@
 #include <RecordingScriptingInterface.h>
 #include <ScriptCache.h>
 #include <SoundCache.h>
+#include <ScriptEngines.h>
 #include <TextureCache.h>
 #include <Tooltip.h>
 #include <udt/PacketHeaders.h>
@@ -319,6 +320,7 @@ bool setupEssentials(int& argc, char** argv) {
     Setting::init();
 
     // Set dependencies
+    DependencyManager::set<ScriptEngines>();
     DependencyManager::set<recording::Deck>();
     DependencyManager::set<recording::Recorder>();
     DependencyManager::set<AddressManager>();
@@ -402,16 +404,11 @@ Application::Application(int& argc, char** argv, QElapsedTimer& startupTimer) :
     _entityClipboard(new EntityTree()),
     _lastQueriedTime(usecTimestampNow()),
     _mirrorViewRect(QRect(MIRROR_VIEW_LEFT_PADDING, MIRROR_VIEW_TOP_PADDING, MIRROR_VIEW_WIDTH, MIRROR_VIEW_HEIGHT)),
-    _firstRun("firstRun", true),
-    _previousScriptLocation("LastScriptLocation", DESKTOP_LOCATION),
-    _scriptsLocationHandle("scriptsLocation", DESKTOP_LOCATION),
     _fieldOfView("fieldOfView", DEFAULT_FIELD_OF_VIEW_DEGREES),
     _scaleMirror(1.0f),
     _rotateMirror(0.0f),
     _raiseMirror(0.0f),
     _enableProcessOctreeThread(true),
-    _runningScriptsWidget(NULL),
-    _runningScriptsWidgetWasVisible(false),
     _lastNackTime(usecTimestampNow()),
     _lastSendDownstreamAudioStats(usecTimestampNow()),
     _aboutToQuit(false),
@@ -451,7 +448,6 @@ Application::Application(int& argc, char** argv, QElapsedTimer& startupTimer) :
 
     _bookmarks = new Bookmarks();  // Before setting up the menu
 
-    _runningScriptsWidget = new RunningScriptsWidget(_window);
     _renderEngine->addTask(make_shared<RenderDeferredTask>());
     _renderEngine->registerScene(_main3DScene);
 
@@ -598,6 +594,30 @@ Application::Application(int& argc, char** argv, QElapsedTimer& startupTimer) :
     connect(addressManager.data(), &AddressManager::hostChanged, this, &Application::updateWindowTitle);
     connect(this, &QCoreApplication::aboutToQuit, addressManager.data(), &AddressManager::storeCurrentAddress);
 
+    auto scriptEngines = DependencyManager::get<ScriptEngines>().data();
+    scriptEngines->registerScriptInitializer([this](ScriptEngine* engine){
+        registerScriptEngineWithApplicationServices(engine);
+    });
+
+    connect(scriptEngines, &ScriptEngines::scriptCountChanged, scriptEngines, [this] {
+        auto scriptEngines = DependencyManager::get<ScriptEngines>();
+        if (scriptEngines->getRunningScripts().isEmpty()) {
+            getMyAvatar()->clearScriptableSettings();
+        }
+    }, Qt::QueuedConnection);
+
+    connect(scriptEngines, &ScriptEngines::scriptsReloading, scriptEngines, [this] {
+        getEntities()->reloadEntityScripts();
+    }, Qt::QueuedConnection);
+
+    connect(scriptEngines, &ScriptEngines::scriptLoadError, 
+        scriptEngines, [](const QString& filename, const QString& error){
+        OffscreenUi::warning(nullptr, "Error Loading Script", filename + " failed to load.");
+    }, Qt::QueuedConnection);
+
+    _runningScriptsWidget = new RunningScriptsWidget(_window);
+
+
 #ifdef _WIN32
     WSADATA WsaData;
     int wsaresult = WSAStartup(MAKEWORD(2, 2), &WsaData);
@@ -677,9 +697,6 @@ Application::Application(int& argc, char** argv, QElapsedTimer& startupTimer) :
 
     _overlays.init(); // do this before scripts load
 
-    _runningScriptsWidget->setRunningScripts(getRunningScripts());
-
-    connect(this, SIGNAL(aboutToQuit()), this, SLOT(saveScripts()));
     connect(this, SIGNAL(aboutToQuit()), this, SLOT(aboutToQuit()));
 
     // hook up bandwidth estimator
@@ -846,18 +863,10 @@ Application::Application(int& argc, char** argv, QElapsedTimer& startupTimer) :
     userInputMapper->registerDevice(_keyboardMouseDevice->getInputDevice());
     userInputMapper->loadDefaultMapping(userInputMapper->getStandardDeviceID());
 
-    // check first run...
-    if (_firstRun.get()) {
-        qCDebug(interfaceapp) << "This is a first run...";
-        // clear the scripts, and set out script to our default scripts
-        clearScriptsBeforeRunning();
-        loadScript(DEFAULT_SCRIPTS_JS_URL);
-
-        _firstRun.set(false);
-    } else {
-        // do this as late as possible so that all required subsystems are initialized
-        loadScripts();
-    }
+    // force the model the look at the correct directory (weird order of operations issue)
+    scriptEngines->setScriptsLocation(scriptEngines->getScriptsLocation());
+    // do this as late as possible so that all required subsystems are initialized
+    scriptEngines->loadScripts();
 
     loadSettings();
     int SAVE_SETTINGS_INTERVAL = 10 * MSECS_PER_SECOND; // Let's save every seconds for now
@@ -1016,7 +1025,9 @@ void Application::cleanupBeforeQuit() {
     nodeList->getPacketReceiver().setShouldDropPackets(true);
 
     getEntities()->shutdown(); // tell the entities system we're shutting down, so it will stop running scripts
-    ScriptEngine::stopAllScripts(this); // stop all currently running global scripts
+    DependencyManager::get<ScriptEngines>()->saveScripts();
+    DependencyManager::get<ScriptEngines>()->shutdownScripting(); // stop all currently running global scripts
+    DependencyManager::destroy<ScriptEngines>(); 
 
     // first stop all timers directly or by invokeMethod
     // depending on what thread they run in
@@ -1191,8 +1202,9 @@ void Application::initializeUi() {
     connect(engine, &QQmlEngine::quit, [] {
         qApp->quit();
     });
-    rootContext->setContextProperty("Audio", &AudioScriptingInterface::getInstance());
+
     rootContext->setContextProperty("AnimationCache", DependencyManager::get<AnimationCache>().data());
+    rootContext->setContextProperty("Audio", &AudioScriptingInterface::getInstance());
     rootContext->setContextProperty("Controller", DependencyManager::get<controller::ScriptingInterface>().data());
     rootContext->setContextProperty("Entities", DependencyManager::get<EntityScriptingInterface>().data());
     rootContext->setContextProperty("MyAvatar", getMyAvatar());
@@ -1219,6 +1231,7 @@ void Application::initializeUi() {
     rootContext->setContextProperty("Menu", MenuScriptingInterface::getInstance());
     rootContext->setContextProperty("Stats", Stats::getInstance());
     rootContext->setContextProperty("Settings", SettingsScriptingInterface::getInstance());
+    rootContext->setContextProperty("ScriptDiscoveryService", DependencyManager::get<ScriptEngines>().data());
     rootContext->setContextProperty("AudioDevice", AudioDeviceScriptingInterface::getInstance());
     rootContext->setContextProperty("AnimationCache", DependencyManager::get<AnimationCache>().data());
     rootContext->setContextProperty("SoundCache", DependencyManager::get<SoundCache>().data());
@@ -1233,7 +1246,6 @@ void Application::initializeUi() {
     rootContext->setContextProperty("HMD", DependencyManager::get<HMDScriptingInterface>().data());
     rootContext->setContextProperty("Scene", DependencyManager::get<SceneScriptingInterface>().data());
     rootContext->setContextProperty("Render", DependencyManager::get<RenderScriptingInterface>().data());
-    rootContext->setContextProperty("ScriptDiscoveryService", this->getRunningScriptsWidget());
 
     _glWidget->installEventFilter(offscreenUi.data());
     VrMenu::load();
@@ -3437,29 +3449,6 @@ bool Application::isHMDMode() const {
 }
 float Application::getTargetFrameRate() { return getActiveDisplayPlugin()->getTargetFrameRate(); }
 
-QRect Application::getDesirableApplicationGeometry() {
-    QRect applicationGeometry = getWindow()->geometry();
-
-    // If our parent window is on the HMD, then don't use its geometry, instead use
-    // the "main screen" geometry.
-    HMDToolsDialog* hmdTools = DependencyManager::get<DialogsManager>()->getHMDToolsDialog();
-    if (hmdTools && hmdTools->hasHMDScreen()) {
-        QScreen* hmdScreen = hmdTools->getHMDScreen();
-        QWindow* appWindow = getWindow()->windowHandle();
-        QScreen* appScreen = appWindow->screen();
-
-        // if our app's screen is the hmd screen, we don't want to place the
-        // running scripts widget on it. So we need to pick a better screen.
-        // we will use the screen for the HMDTools since it's a guarenteed
-        // better screen.
-        if (appScreen == hmdScreen) {
-            QScreen* betterScreen = hmdTools->windowHandle()->screen();
-            applicationGeometry = betterScreen->geometry();
-        }
-    }
-    return applicationGeometry;
-}
-
 /////////////////////////////////////////////////////////////////////////////////////
 // loadViewFrustum()
 //
@@ -4163,48 +4152,6 @@ int Application::processOctreeStats(ReceivedMessage& message, SharedNodePointer
 void Application::packetSent(quint64 length) {
 }
 
-const QString SETTINGS_KEY = "Settings";
-
-void Application::loadScripts() {
-    // loads all saved scripts
-    Settings settings;
-    int size = settings.beginReadArray(SETTINGS_KEY);
-    for (int i = 0; i < size; ++i){
-        settings.setArrayIndex(i);
-        QString string = settings.value("script").toString();
-        if (!string.isEmpty()) {
-            loadScript(string);
-        }
-    }
-    settings.endArray();
-}
-
-void Application::clearScriptsBeforeRunning() {
-    // clears all scripts from the settingsSettings settings;
-    Settings settings;
-    settings.beginWriteArray(SETTINGS_KEY);
-    settings.remove("");
-}
-
-void Application::saveScripts() {
-    // Saves all currently running user-loaded scripts
-    Settings settings;
-    settings.beginWriteArray(SETTINGS_KEY);
-    settings.remove("");
-
-    QStringList runningScripts = getRunningScripts();
-    int i = 0;
-    for (auto it = runningScripts.begin(); it != runningScripts.end(); ++it) {
-        if (getScriptEngine(*it)->isUserLoaded()) {
-            settings.setArrayIndex(i);
-            settings.setValue("script", *it);
-            ++i;
-        }
-    }
-    settings.endArray();
-}
-
-
 void Application::registerScriptEngineWithApplicationServices(ScriptEngine* scriptEngine) {
     // setup the packet senders and jurisdiction listeners of the script engine's scripting interfaces so
     // we can use the same ones from the application.
@@ -4231,11 +4178,6 @@ void Application::registerScriptEngineWithApplicationServices(ScriptEngine* scri
     scriptEngine->registerGlobalObject("Clipboard", clipboardScriptable);
     connect(scriptEngine, &ScriptEngine::finished, clipboardScriptable, &ClipboardScriptingInterface::deleteLater);
 
-    connect(scriptEngine, &ScriptEngine::finished, this, &Application::scriptFinished, Qt::DirectConnection);
-
-    connect(scriptEngine, SIGNAL(loadScript(const QString&, bool)), this, SLOT(loadScript(const QString&, bool)));
-    connect(scriptEngine, SIGNAL(reloadScript(const QString&, bool)), this, SLOT(reloadScript(const QString&, bool)));
-
     scriptEngine->registerGlobalObject("Overlays", &_overlays);
     qScriptRegisterMetaType(scriptEngine, OverlayPropertyResultToScriptValue, OverlayPropertyResultFromScriptValue);
     qScriptRegisterMetaType(scriptEngine, RayToOverlayIntersectionResultToScriptValue,
@@ -4283,7 +4225,7 @@ void Application::registerScriptEngineWithApplicationServices(ScriptEngine* scri
     scriptEngine->registerGlobalObject("Scene", DependencyManager::get<SceneScriptingInterface>().data());
     scriptEngine->registerGlobalObject("Render", DependencyManager::get<RenderScriptingInterface>().data());
 
-    scriptEngine->registerGlobalObject("ScriptDiscoveryService", this->getRunningScriptsWidget());
+    scriptEngine->registerGlobalObject("ScriptDiscoveryService", DependencyManager::get<ScriptEngines>().data());
 }
 
 bool Application::canAcceptURL(const QString& urlString) const {
@@ -4389,7 +4331,7 @@ bool Application::askToLoadScript(const QString& scriptFilenameOrURL) {
 
     if (reply == QMessageBox::Yes) {
         qCDebug(interfaceapp) << "Chose to run the script: " << scriptFilenameOrURL;
-        loadScript(scriptFilenameOrURL);
+        DependencyManager::get<ScriptEngines>()->loadScript(scriptFilenameOrURL);
     } else {
         qCDebug(interfaceapp) << "Declined to run the script: " << scriptFilenameOrURL;
     }
@@ -4562,186 +4504,6 @@ bool Application::displayAvatarAttachmentConfirmationDialog(const QString& name)
     }
 }
 
-ScriptEngine* Application::loadScript(const QString& scriptFilename, bool isUserLoaded,
-                                      bool loadScriptFromEditor, bool activateMainWindow, bool reload) {
-
-    if (isAboutToQuit()) {
-        return NULL;
-    }
-
-    QUrl scriptUrl(scriptFilename);
-    const QString& scriptURLString = scriptUrl.toString();
-    {
-        QReadLocker lock(&_scriptEnginesHashLock);
-        if (_scriptEnginesHash.contains(scriptURLString) && loadScriptFromEditor
-            && !_scriptEnginesHash[scriptURLString]->isFinished()) {
-
-            return _scriptEnginesHash[scriptURLString];
-        }
-    }
-
-    ScriptEngine* scriptEngine = new ScriptEngine(NO_SCRIPT, "", &_controllerScriptingInterface);
-    scriptEngine->setUserLoaded(isUserLoaded);
-
-    if (scriptFilename.isNull()) {
-        // This appears to be the script engine used by the script widget's evaluation window before the file has been saved...
-
-        // this had better be the script editor (we should de-couple so somebody who thinks they are loading a script
-        // doesn't just get an empty script engine)
-
-        // we can complete setup now since there isn't a script we have to load
-        registerScriptEngineWithApplicationServices(scriptEngine);
-        scriptEngine->runInThread();
-    } else {
-        // connect to the appropriate signals of this script engine
-        connect(scriptEngine, &ScriptEngine::scriptLoaded, this, &Application::handleScriptEngineLoaded);
-        connect(scriptEngine, &ScriptEngine::errorLoadingScript, this, &Application::handleScriptLoadError);
-
-        // get the script engine object to load the script at the designated script URL
-        scriptEngine->loadURL(scriptUrl, reload);
-    }
-
-    // restore the main window's active state
-    if (activateMainWindow && !loadScriptFromEditor) {
-        _window->activateWindow();
-    }
-
-    return scriptEngine;
-}
-
-void Application::reloadScript(const QString& scriptName, bool isUserLoaded) {
-    loadScript(scriptName, isUserLoaded, false, false, true);
-}
-
-// FIXME - change to new version of ScriptCache loading notification
-void Application::handleScriptEngineLoaded(const QString& scriptFilename) {
-    ScriptEngine* scriptEngine = qobject_cast<ScriptEngine*>(sender());
-
-    {
-        QWriteLocker lock(&_scriptEnginesHashLock);
-        _scriptEnginesHash.insertMulti(scriptFilename, scriptEngine);
-    }
-
-    _runningScriptsWidget->setRunningScripts(getRunningScripts());
-    UserActivityLogger::getInstance().loadedScript(scriptFilename);
-
-    // register our application services and set it off on its own thread
-    registerScriptEngineWithApplicationServices(scriptEngine);
-    scriptEngine->runInThread();
-}
-
-// FIXME - change to new version of ScriptCache loading notification
-void Application::handleScriptLoadError(const QString& scriptFilename) {
-    qCDebug(interfaceapp) << "Application::loadScript(), script failed to load...";
-    OffscreenUi::warning(getWindow(), "Error Loading Script", scriptFilename + " failed to load.");
-}
-
-QStringList Application::getRunningScripts() {
-    QReadLocker lock(&_scriptEnginesHashLock);
-    return _scriptEnginesHash.keys();
-}
-
-ScriptEngine* Application::getScriptEngine(const QString& scriptHash) {
-    QReadLocker lock(&_scriptEnginesHashLock);
-    return _scriptEnginesHash.value(scriptHash, nullptr);
-}
-
-void Application::scriptFinished(const QString& scriptName, ScriptEngine* engine) {
-    bool removed = false;
-    {
-        QWriteLocker lock(&_scriptEnginesHashLock);
-        const QString& scriptURLString = QUrl(scriptName).toString();
-        for (auto it = _scriptEnginesHash.find(scriptURLString); it != _scriptEnginesHash.end(); ++it) {
-            if (it.value() == engine) {
-                _scriptEnginesHash.erase(it);
-                removed = true;
-                break;
-            }
-        }
-    }
-    if (removed) {
-        postLambdaEvent([this, scriptName]() {
-            _runningScriptsWidget->scriptStopped(scriptName);
-            _runningScriptsWidget->setRunningScripts(getRunningScripts());
-        });
-    }
-}
-
-void Application::stopAllScripts(bool restart) {
-    {
-        QReadLocker lock(&_scriptEnginesHashLock);
-
-        if (restart) {
-            // Delete all running scripts from cache so that they are re-downloaded when they are restarted
-            auto scriptCache = DependencyManager::get<ScriptCache>();
-            for (QHash<QString, ScriptEngine*>::const_iterator it = _scriptEnginesHash.constBegin();
-            it != _scriptEnginesHash.constEnd(); it++) {
-                if (!it.value()->isFinished()) {
-                    scriptCache->deleteScript(it.key());
-                }
-            }
-        }
-
-        // Stop and possibly restart all currently running scripts
-        for (QHash<QString, ScriptEngine*>::const_iterator it = _scriptEnginesHash.constBegin();
-                it != _scriptEnginesHash.constEnd(); it++) {
-            if (it.value()->isFinished()) {
-                continue;
-            }
-            if (restart && it.value()->isUserLoaded()) {
-                connect(it.value(), &ScriptEngine::finished, this, [this](QString scriptName, ScriptEngine* engine) {
-                    reloadScript(scriptName);
-                });
-            }
-            QMetaObject::invokeMethod(it.value(), "stop");
-            //it.value()->stop();
-            qCDebug(interfaceapp) << "stopping script..." << it.key();
-        }
-    }
-    getMyAvatar()->clearScriptableSettings();
-}
-
-bool Application::stopScript(const QString& scriptHash, bool restart) {
-    bool stoppedScript = false;
-    {
-        QReadLocker lock(&_scriptEnginesHashLock);
-        if (_scriptEnginesHash.contains(scriptHash)) {
-            ScriptEngine* scriptEngine = _scriptEnginesHash[scriptHash];
-            if (restart) {
-                auto scriptCache = DependencyManager::get<ScriptCache>();
-                scriptCache->deleteScript(QUrl(scriptHash));
-                connect(scriptEngine, &ScriptEngine::finished, this, [this](QString scriptName, ScriptEngine* engine) {
-                    reloadScript(scriptName);
-                });
-            }
-            scriptEngine->stop();
-            stoppedScript = true;
-            qCDebug(interfaceapp) << "stopping script..." << scriptHash;
-        }
-    }
-    if (_scriptEnginesHash.empty()) {
-        getMyAvatar()->clearScriptableSettings();
-    }
-    return stoppedScript;
-}
-
-void Application::reloadAllScripts() {
-    DependencyManager::get<ScriptCache>()->clearCache();
-    getEntities()->reloadEntityScripts();
-    stopAllScripts(true);
-}
-
-void Application::reloadOneScript(const QString& scriptName) {
-    stopScript(scriptName, true);
-}
-
-void Application::loadDefaultScripts() {
-    QReadLocker lock(&_scriptEnginesHashLock);
-    if (!_scriptEnginesHash.contains(DEFAULT_SCRIPTS_JS_URL)) {
-        loadScript(DEFAULT_SCRIPTS_JS_URL);
-    }
-}
-
 void Application::toggleRunningScriptsWidget() {
     if (_runningScriptsWidget->isVisible()) {
         if (_runningScriptsWidget->hasFocus()) {
@@ -4799,27 +4561,17 @@ void Application::domainSettingsReceived(const QJsonObject& domainSettingsObject
     qCDebug(interfaceapp) << "Destination wallet UUID for edit payments is" << voxelWalletUUID;
 }
 
-QString Application::getPreviousScriptLocation() {
-    return _previousScriptLocation.get();
-}
-
-void Application::setPreviousScriptLocation(const QString& previousScriptLocation) {
-    _previousScriptLocation.set(previousScriptLocation);
-}
-
 void Application::loadDialog() {
-
-    QString fileNameString = QFileDialog::getOpenFileName(_glWidget,
-                                                          tr("Open Script"),
-                                                          getPreviousScriptLocation(),
-                                                          tr("JavaScript Files (*.js)"));
+    // To be migratd to QML
+    QString fileNameString = QFileDialog::getOpenFileName(
+        _glWidget, tr("Open Script"), "", tr("JavaScript Files (*.js)"));
     if (!fileNameString.isEmpty()) {
-        setPreviousScriptLocation(fileNameString);
-        loadScript(fileNameString);
+        DependencyManager::get<ScriptEngines>()->loadScript(fileNameString);
     }
 }
 
 void Application::loadScriptURLDialog() {
+    // To be migratd to QML
     QInputDialog scriptURLDialog(getWindow());
     scriptURLDialog.setWindowTitle("Open and Run Script URL");
     scriptURLDialog.setLabelText("Script:");
@@ -4835,19 +4587,10 @@ void Application::loadScriptURLDialog() {
             // the user input a new hostname, use that
             newScript = scriptURLDialog.textValue();
         }
-        loadScript(newScript);
+        DependencyManager::get<ScriptEngines>()->loadScript(newScript);
     }
 }
 
-QString Application::getScriptsLocation() {
-    return _scriptsLocationHandle.get();
-}
-
-void Application::setScriptsLocation(const QString& scriptsLocation) {
-    _scriptsLocationHandle.set(scriptsLocation);
-    emit scriptLocationChanged(scriptsLocation);
-}
-
 void Application::toggleLogDialog() {
     if (! _logDialog) {
         _logDialog = new LogDialog(_glWidget, getLogger());
diff --git a/interface/src/Application.h b/interface/src/Application.h
index 39e5453d1d..9237373778 100644
--- a/interface/src/Application.h
+++ b/interface/src/Application.h
@@ -106,10 +106,6 @@ public:
 
     void postLambdaEvent(std::function<void()> f);
 
-    void loadScripts();
-    QString getPreviousScriptLocation();
-    void setPreviousScriptLocation(const QString& previousScriptLocation);
-    void clearScriptsBeforeRunning();
     void initializeGL();
     void initializeUi();
     void paintGL();
@@ -197,9 +193,6 @@ public:
 
     NodeToJurisdictionMap& getEntityServerJurisdictions() { return _entityServerJurisdictions; }
 
-    QStringList getRunningScripts();
-    ScriptEngine* getScriptEngine(const QString& scriptHash);
-
     float getRenderResolutionScale() const;
 
     bool isAboutToQuit() const { return _aboutToQuit; }
@@ -212,14 +205,8 @@ public:
     glm::mat4 getEyeOffset(int eye) const;
     glm::mat4 getEyeProjection(int eye) const;
 
-    QRect getDesirableApplicationGeometry();
-    RunningScriptsWidget* getRunningScriptsWidget() { return _runningScriptsWidget; }
-
     Bookmarks* getBookmarks() const { return _bookmarks; }
 
-    QString getScriptsLocation();
-    void setScriptsLocation(const QString& scriptsLocation);
-
     virtual bool canAcceptURL(const QString& url) const override;
     virtual bool acceptURL(const QString& url, bool defaultUpload = false) override;
 
@@ -241,8 +228,6 @@ public:
     float getAverageSimsPerSecond();
 
 signals:
-    void scriptLocationChanged(const QString& newPath);
-
     void svoImportRequested(const QString& url);
 
     void checkBackgroundDownloads();
@@ -263,14 +248,6 @@ public slots:
     void loadDialog();
     void loadScriptURLDialog();
     void toggleLogDialog();
-
-    ScriptEngine* loadScript(const QString& scriptFilename = QString(), bool isUserLoaded = true,
-        bool loadScriptFromEditor = false, bool activateMainWindow = false, bool reload = false);
-    void stopAllScripts(bool restart = false);
-    bool stopScript(const QString& scriptHash, bool restart = false);
-    void reloadAllScripts();
-    void reloadOneScript(const QString& scriptName);
-    void loadDefaultScripts();
     void toggleRunningScriptsWidget();
 
     void showFriendsWindow();
@@ -313,9 +290,6 @@ private slots:
     void idle(uint64_t now);
     void aboutToQuit();
 
-    void handleScriptEngineLoaded(const QString& scriptFilename);
-    void handleScriptLoadError(const QString& scriptFilename);
-
     void connectedToDomain(const QString& hostname);
 
     void audioMuteToggled();
@@ -331,10 +305,6 @@ private slots:
     void loadSettings();
     void saveSettings();
     
-    void scriptFinished(const QString& scriptName, ScriptEngine* engine);
-    void saveScripts();
-    void reloadScript(const QString& scriptName, bool isUserLoaded = true);
-    
     bool acceptSnapshot(const QString& urlString);
     bool askToSetAvatarUrl(const QString& url);
     bool askToLoadScript(const QString& scriptFilenameOrURL);
@@ -468,9 +438,6 @@ private:
     Camera _mirrorCamera;                        // Cammera for mirror view
     QRect _mirrorViewRect;
 
-    Setting::Handle<bool> _firstRun;
-    Setting::Handle<QString> _previousScriptLocation;
-    Setting::Handle<QString> _scriptsLocationHandle;
     Setting::Handle<float> _fieldOfView;
 
     float _scaleMirror;
@@ -499,12 +466,7 @@ private:
 
     TouchEvent _lastTouchEvent;
 
-    QReadWriteLock _scriptEnginesHashLock;
-    RunningScriptsWidget* _runningScriptsWidget;
-    QHash<QString, ScriptEngine*> _scriptEnginesHash;
-    bool _runningScriptsWidgetWasVisible;
-    QString _scriptsLocation;
-
+    RunningScriptsWidget* _runningScriptsWidget{ nullptr };
     quint64 _lastNackTime;
     quint64 _lastSendDownstreamAudioStats;
     
diff --git a/interface/src/Menu.cpp b/interface/src/Menu.cpp
index 6373b3fdb2..eec04d4640 100644
--- a/interface/src/Menu.cpp
+++ b/interface/src/Menu.cpp
@@ -21,6 +21,7 @@
 #include <SettingHandle.h>
 #include <UserActivityLogger.h>
 #include <VrMenu.h>
+#include <ScriptEngines.h>
 
 #include "Application.h"
 #include "AccountManager.h"
@@ -114,13 +115,15 @@ Menu::Menu() {
         Qt::CTRL | Qt::SHIFT | Qt::Key_O, qApp, SLOT(loadScriptURLDialog()),
         QAction::NoRole, UNSPECIFIED_POSITION, "Advanced");
 
+    auto scriptEngines = DependencyManager::get<ScriptEngines>();
     // Edit > Stop All Scripts... [advanced]
-    addActionToQMenuAndActionHash(editMenu, MenuOption::StopAllScripts, 0, qApp, SLOT(stopAllScripts()),
+    addActionToQMenuAndActionHash(editMenu, MenuOption::StopAllScripts, 0, 
+        scriptEngines.data(), SLOT(stopAllScripts()),
         QAction::NoRole, UNSPECIFIED_POSITION, "Advanced");
 
     // Edit > Reload All Scripts... [advanced]
     addActionToQMenuAndActionHash(editMenu, MenuOption::ReloadAllScripts, Qt::CTRL | Qt::Key_R,
-        qApp, SLOT(reloadAllScripts()),
+        scriptEngines.data(), SLOT(reloadAllScripts()),
         QAction::NoRole, UNSPECIFIED_POSITION, "Advanced");
 
     // Edit > Scripts Editor... [advanced]
diff --git a/interface/src/ui/HMDToolsDialog.cpp b/interface/src/ui/HMDToolsDialog.cpp
index c1ea541864..f9fc444d4b 100644
--- a/interface/src/ui/HMDToolsDialog.cpp
+++ b/interface/src/ui/HMDToolsDialog.cpp
@@ -79,9 +79,6 @@ HMDToolsDialog::HMDToolsDialog(QWidget* parent) :
     // what screens we're allowed on
     watchWindow(windowHandle());
     auto dialogsManager = DependencyManager::get<DialogsManager>();
-    if (qApp->getRunningScriptsWidget()) {
-        watchWindow(qApp->getRunningScriptsWidget()->windowHandle());
-    }
     if (qApp->getToolWindow()) {
         watchWindow(qApp->getToolWindow()->windowHandle());
     }
diff --git a/interface/src/ui/JSConsole.cpp b/interface/src/ui/JSConsole.cpp
index 2d34ba5608..5d197f5ddc 100644
--- a/interface/src/ui/JSConsole.cpp
+++ b/interface/src/ui/JSConsole.cpp
@@ -15,6 +15,7 @@
 #include <QScrollBar>
 #include <QtConcurrent/QtConcurrentRun>
 
+#include <ScriptEngines.h>
 #include <PathUtils.h>
 
 #include "Application.h"
@@ -84,7 +85,7 @@ void JSConsole::setScriptEngine(ScriptEngine* scriptEngine) {
 
     // if scriptEngine is NULL then create one and keep track of it using _ownScriptEngine
     _ownScriptEngine = scriptEngine == NULL;
-    _scriptEngine = _ownScriptEngine ? qApp->loadScript(QString(), false) : scriptEngine;
+    _scriptEngine = _ownScriptEngine ? DependencyManager::get<ScriptEngines>()->loadScript(QString(), false) : scriptEngine;
 
     connect(_scriptEngine, SIGNAL(printedMessage(const QString&)), this, SLOT(handlePrint(const QString&)));
     connect(_scriptEngine, SIGNAL(errorMessage(const QString&)), this, SLOT(handleError(const QString&)));
diff --git a/interface/src/ui/PreferencesDialog.cpp b/interface/src/ui/PreferencesDialog.cpp
index 216c11a05c..b5e24fef1e 100644
--- a/interface/src/ui/PreferencesDialog.cpp
+++ b/interface/src/ui/PreferencesDialog.cpp
@@ -17,6 +17,7 @@
 #include <devices/DdeFaceTracker.h>
 #include <devices/Faceshift.h>
 #include <NetworkingConstants.h>
+#include <ScriptEngines.h>
 
 #include "Application.h"
 #include "DialogsManager.h"
@@ -44,7 +45,9 @@ PreferencesDialog::PreferencesDialog(QWidget* parent) :
 
     connect(ui.buttonBrowseLocation, &QPushButton::clicked, this, &PreferencesDialog::openSnapshotLocationBrowser);
     connect(ui.buttonBrowseScriptsLocation, &QPushButton::clicked, this, &PreferencesDialog::openScriptsLocationBrowser);
-    connect(ui.buttonReloadDefaultScripts, &QPushButton::clicked, qApp, &Application::loadDefaultScripts);
+    connect(ui.buttonReloadDefaultScripts, &QPushButton::clicked, [] {
+        DependencyManager::get<ScriptEngines>()->loadDefaultScripts();
+    });
 
     connect(ui.buttonChangeAppearance, &QPushButton::clicked, this, &PreferencesDialog::openFullAvatarModelBrowser);
     connect(ui.appearanceDescription, &QLineEdit::editingFinished, this, &PreferencesDialog::changeFullAvatarURL);
@@ -171,7 +174,7 @@ void PreferencesDialog::loadPreferences() {
 
     ui.snapshotLocationEdit->setText(Snapshot::snapshotsLocation.get());
 
-    ui.scriptsLocationEdit->setText(qApp->getScriptsLocation());
+    ui.scriptsLocationEdit->setText(DependencyManager::get<ScriptEngines>()->getScriptsLocation());
 
     ui.pupilDilationSlider->setValue(myAvatar->getHead()->getPupilDilation() *
                                      ui.pupilDilationSlider->maximum());
@@ -265,7 +268,7 @@ void PreferencesDialog::savePreferences() {
     }
 
     if (!ui.scriptsLocationEdit->text().isEmpty() && QDir(ui.scriptsLocationEdit->text()).exists()) {
-        qApp->setScriptsLocation(ui.scriptsLocationEdit->text());
+        DependencyManager::get<ScriptEngines>()->setScriptsLocation(ui.scriptsLocationEdit->text());
     }
 
     myAvatar->getHead()->setPupilDilation(ui.pupilDilationSlider->value() / (float)ui.pupilDilationSlider->maximum());
diff --git a/interface/src/ui/RunningScriptsWidget.cpp b/interface/src/ui/RunningScriptsWidget.cpp
index 3752ea2176..483d467f01 100644
--- a/interface/src/ui/RunningScriptsWidget.cpp
+++ b/interface/src/ui/RunningScriptsWidget.cpp
@@ -22,8 +22,10 @@
 #include <QWindow>
 
 #include <PathUtils.h>
+#include <ScriptEngines.h>
 
 #include "Application.h"
+#include "MainWindow.h"
 #include "Menu.h"
 #include "ScriptsModel.h"
 #include "UIUtil.h"
@@ -33,57 +35,55 @@ RunningScriptsWidget::RunningScriptsWidget(QWidget* parent) :
             Qt::WindowCloseButtonHint),
     ui(new Ui::RunningScriptsWidget),
     _reloadSignalMapper(this),
-    _stopSignalMapper(this),
-    _scriptsModelFilter(this),
-    _scriptsModel(this) {
+    _stopSignalMapper(this) {
     ui->setupUi(this);
 
     setAttribute(Qt::WA_DeleteOnClose, false);
 
     ui->filterLineEdit->installEventFilter(this);
 
-    connect(&_scriptsModelFilter, &QSortFilterProxyModel::modelReset,
+    auto scriptEngines = DependencyManager::get<ScriptEngines>().data();
+    connect(scriptEngines->scriptsModelFilter(), &QSortFilterProxyModel::modelReset,
             this, &RunningScriptsWidget::selectFirstInList);
 
     // FIXME: menu isn't prepared at this point.
     //QString shortcutText = Menu::getInstance()->getActionForOption(MenuOption::ReloadAllScripts)->shortcut().toString(QKeySequence::NativeText);
     //ui->tipLabel->setText("Tip: Use " + shortcutText + " to reload all scripts.");
-
-    _scriptsModelFilter.setSourceModel(&_scriptsModel);
-    _scriptsModelFilter.sort(0, Qt::AscendingOrder);
-    _scriptsModelFilter.setDynamicSortFilter(true);
-    ui->scriptTreeView->setModel(&_scriptsModelFilter);
+    ui->scriptTreeView->setModel(scriptEngines->scriptsModelFilter());
 
     connect(ui->filterLineEdit, &QLineEdit::textChanged, this, &RunningScriptsWidget::updateFileFilter);
     connect(ui->scriptTreeView, &QTreeView::doubleClicked, this, &RunningScriptsWidget::loadScriptFromList);
 
-    connect(ui->reloadAllButton, &QPushButton::clicked, qApp, &Application::reloadAllScripts);
-    connect(ui->stopAllButton, &QPushButton::clicked, this, &RunningScriptsWidget::allScriptsStopped);
+    connect(ui->reloadAllButton, &QPushButton::clicked, scriptEngines, &ScriptEngines::reloadAllScripts);
+    connect(ui->stopAllButton, &QPushButton::clicked, scriptEngines, &ScriptEngines::stopAllScripts);
     connect(ui->loadScriptFromDiskButton, &QPushButton::clicked, qApp, &Application::loadDialog);
     connect(ui->loadScriptFromURLButton, &QPushButton::clicked, qApp, &Application::loadScriptURLDialog);
     connect(&_reloadSignalMapper, static_cast<void(QSignalMapper::*)(const QString&)>(&QSignalMapper::mapped),
-            qApp, &Application::reloadOneScript);
-
+        [scriptEngines](const QString& scriptName) { scriptEngines->stopScript(scriptName, true); });
     connect(&_stopSignalMapper, static_cast<void(QSignalMapper::*)(const QString&)>(&QSignalMapper::mapped),
-            [](const QString& script) { qApp->stopScript(script); });
+        [scriptEngines](const QString& scriptName) { scriptEngines->stopScript(scriptName); });
 
+    setRunningScripts(scriptEngines->getRunningScripts());
+    connect(scriptEngines, &ScriptEngines::scriptCountChanged, scriptEngines, [this, scriptEngines] { 
+        setRunningScripts(scriptEngines->getRunningScripts()); 
+    }, Qt::QueuedConnection);
     UIUtil::scaleWidgetFontSizes(this);
 }
 
 RunningScriptsWidget::~RunningScriptsWidget() {
     delete ui;
-    _scriptsModel.deleteLater();
 }
 
 void RunningScriptsWidget::updateFileFilter(const QString& filter) {
     QRegExp regex("^.*" + QRegExp::escape(filter) + ".*$", Qt::CaseInsensitive);
-    _scriptsModelFilter.setFilterRegExp(regex);
+    DependencyManager::get<ScriptEngines>()->scriptsModelFilter()->setFilterRegExp(regex);
     selectFirstInList();
 }
 
 void RunningScriptsWidget::loadScriptFromList(const QModelIndex& index) {
-    QVariant scriptFile = _scriptsModelFilter.data(index, ScriptsModel::ScriptPath);
-    qApp->loadScript(scriptFile.toString());
+    auto scriptEngines = DependencyManager::get<ScriptEngines>();
+    QVariant scriptFile = scriptEngines->scriptsModelFilter()->data(index, ScriptsModel::ScriptPath);
+    scriptEngines->loadScript(scriptFile.toString());
 }
 
 void RunningScriptsWidget::loadSelectedScript() {
@@ -172,7 +172,7 @@ void RunningScriptsWidget::showEvent(QShowEvent* event) {
         ui->filterLineEdit->setFocus();
     }
 
-    QRect parentGeometry = qApp->getDesirableApplicationGeometry();
+    QRect parentGeometry = qApp->getWindow()->geometry();
     int titleBarHeight = UIUtil::getWindowTitleBarHeight(this);
     int topMargin = titleBarHeight;
 
@@ -183,8 +183,9 @@ void RunningScriptsWidget::showEvent(QShowEvent* event) {
 }
 
 void RunningScriptsWidget::selectFirstInList() {
-    if (_scriptsModelFilter.rowCount() > 0) {
-        ui->scriptTreeView->setCurrentIndex(_scriptsModelFilter.index(0, 0));
+    auto model = DependencyManager::get<ScriptEngines>()->scriptsModelFilter();
+    if (model->rowCount() > 0) {
+        ui->scriptTreeView->setCurrentIndex(model->index(0, 0));
     }
 }
 
@@ -217,90 +218,5 @@ void RunningScriptsWidget::keyPressEvent(QKeyEvent *keyEvent) {
 }
 
 void RunningScriptsWidget::allScriptsStopped() {
-    qApp->stopAllScripts();
-}
-
-QVariantList RunningScriptsWidget::getRunning() {
-    const int WINDOWS_DRIVE_LETTER_SIZE = 1;
-    QVariantList result;
-    foreach(const QString& runningScript, qApp->getRunningScripts()) {
-        QUrl runningScriptURL = QUrl(runningScript);
-        if (runningScriptURL.scheme().size() <= WINDOWS_DRIVE_LETTER_SIZE) {
-            runningScriptURL = QUrl::fromLocalFile(runningScriptURL.toDisplayString(QUrl::FormattingOptions(QUrl::FullyEncoded)));
-        }
-        QVariantMap resultNode;
-        resultNode.insert("name", runningScriptURL.fileName());
-        resultNode.insert("url", runningScriptURL.toDisplayString(QUrl::FormattingOptions(QUrl::FullyEncoded)));
-        // The path contains the exact path/URL of the script, which also is used in the stopScript function.
-        resultNode.insert("path", runningScript);
-        resultNode.insert("local", runningScriptURL.isLocalFile());
-        result.append(resultNode);
-    }
-    return result;
-}
-
-QVariantList RunningScriptsWidget::getPublic() {
-    return getPublicChildNodes(NULL);
-}
-
-QVariantList RunningScriptsWidget::getPublicChildNodes(TreeNodeFolder* parent) {
-    QVariantList result;
-    QList<TreeNodeBase*> treeNodes = qApp->getRunningScriptsWidget()->getScriptsModel()
-        ->getFolderNodes(parent);
-    for (int i = 0; i < treeNodes.size(); i++) {
-        TreeNodeBase* node = treeNodes.at(i);
-        if (node->getType() == TREE_NODE_TYPE_FOLDER) {
-            TreeNodeFolder* folder = static_cast<TreeNodeFolder*>(node);
-            QVariantMap resultNode;
-            resultNode.insert("name", node->getName());
-            resultNode.insert("type", "folder");
-            resultNode.insert("children", getPublicChildNodes(folder));
-            result.append(resultNode);
-            continue;
-        }
-        TreeNodeScript* script = static_cast<TreeNodeScript*>(node);
-        if (script->getOrigin() == ScriptOrigin::SCRIPT_ORIGIN_LOCAL) {
-            continue;
-        }
-        QVariantMap resultNode;
-        resultNode.insert("name", node->getName());
-        resultNode.insert("type", "script");
-        resultNode.insert("url", script->getFullPath());
-        result.append(resultNode);
-    }
-    return result;
-}
-
-QVariantList RunningScriptsWidget::getLocal() {
-    QVariantList result;
-    QList<TreeNodeBase*> treeNodes = qApp->getRunningScriptsWidget()->getScriptsModel()
-        ->getFolderNodes(NULL);
-    for (int i = 0; i < treeNodes.size(); i++) {
-        TreeNodeBase* node = treeNodes.at(i);
-        if (node->getType() != TREE_NODE_TYPE_SCRIPT) {
-            continue;
-        }
-        TreeNodeScript* script = static_cast<TreeNodeScript*>(node);
-        if (script->getOrigin() != ScriptOrigin::SCRIPT_ORIGIN_LOCAL) {
-            continue;
-        }
-        QVariantMap resultNode;
-        resultNode.insert("name", node->getName());
-        resultNode.insert("path", script->getFullPath());
-        result.append(resultNode);
-    }
-    return result;
-}
-
-bool RunningScriptsWidget::stopScriptByName(const QString& name) {
-    foreach (const QString& runningScript, qApp->getRunningScripts()) {
-        if (QUrl(runningScript).fileName().toLower() == name.trimmed().toLower()) {
-            return qApp->stopScript(runningScript, false);
-        }
-    }
-    return false;
-}
-
-bool RunningScriptsWidget::stopScript(const QString& name, bool restart) {
-    return qApp->stopScript(name, restart);
+    DependencyManager::get<ScriptEngines>()->stopAllScripts();
 }
diff --git a/interface/src/ui/RunningScriptsWidget.h b/interface/src/ui/RunningScriptsWidget.h
index 9029b13c56..b60586b5e7 100644
--- a/interface/src/ui/RunningScriptsWidget.h
+++ b/interface/src/ui/RunningScriptsWidget.h
@@ -33,24 +33,12 @@ public:
 
     void setRunningScripts(const QStringList& list);
 
-    const ScriptsModel* getScriptsModel() { return &_scriptsModel; }
-
-signals:
-    void scriptStopped(const QString& scriptName);
-
 protected:
     virtual bool eventFilter(QObject* sender, QEvent* event);
 
     virtual void keyPressEvent(QKeyEvent* event);
     virtual void showEvent(QShowEvent* event);
 
-public slots:
-    QVariantList getRunning();
-    QVariantList getPublic();
-    QVariantList getLocal();
-    bool stopScript(const QString& name, bool restart = false);
-    bool stopScriptByName(const QString& name);
-    
 private slots:
     void allScriptsStopped();
     void updateFileFilter(const QString& filter);
@@ -62,9 +50,6 @@ private:
     Ui::RunningScriptsWidget* ui;
     QSignalMapper _reloadSignalMapper;
     QSignalMapper _stopSignalMapper;
-    ScriptsModelFilter _scriptsModelFilter;
-    ScriptsModel _scriptsModel;
-
     QVariantList getPublicChildNodes(TreeNodeFolder* parent);
 };
 
diff --git a/interface/src/ui/ScriptEditorWidget.cpp b/interface/src/ui/ScriptEditorWidget.cpp
index 380b645681..a261c208d7 100644
--- a/interface/src/ui/ScriptEditorWidget.cpp
+++ b/interface/src/ui/ScriptEditorWidget.cpp
@@ -25,6 +25,7 @@
 #include <QTimer>
 #include <QWidget>
 
+#include <ScriptEngines.h>
 #include <NetworkAccessManager.h>
 #include <OffscreenUi.h>
 
@@ -101,17 +102,18 @@ bool ScriptEditorWidget::setRunning(bool run) {
         disconnect(_scriptEngine, &ScriptEngine::finished, this, &ScriptEditorWidget::onScriptFinished);
     }
 
+    auto scriptEngines = DependencyManager::get<ScriptEngines>();
     if (run) {
         const QString& scriptURLString = QUrl(_currentScript).toString();
         // Reload script so that an out of date copy is not retrieved from the cache
-        _scriptEngine = qApp->loadScript(scriptURLString, true, true, false, true);
+        _scriptEngine = scriptEngines->loadScript(scriptURLString, true, true, false, true);
         connect(_scriptEngine, &ScriptEngine::runningStateChanged, this, &ScriptEditorWidget::runningStateChanged);
         connect(_scriptEngine, &ScriptEngine::update, this, &ScriptEditorWidget::onScriptModified);
         connect(_scriptEngine, &ScriptEngine::finished, this, &ScriptEditorWidget::onScriptFinished);
     } else {
         connect(_scriptEngine, &ScriptEngine::finished, this, &ScriptEditorWidget::onScriptFinished);
         const QString& scriptURLString = QUrl(_currentScript).toString();
-        qApp->stopScript(scriptURLString);
+        scriptEngines->stopScript(scriptURLString);
         _scriptEngine = NULL;
     }
     _console->setScriptEngine(_scriptEngine);
@@ -173,7 +175,7 @@ void ScriptEditorWidget::loadFile(const QString& scriptPath) {
         }
     }
     const QString& scriptURLString = QUrl(_currentScript).toString();
-    _scriptEngine = qApp->getScriptEngine(scriptURLString);
+    _scriptEngine = DependencyManager::get<ScriptEngines>()->getScriptEngine(scriptURLString);
     if (_scriptEngine != NULL) {
         connect(_scriptEngine, &ScriptEngine::runningStateChanged, this, &ScriptEditorWidget::runningStateChanged);
         connect(_scriptEngine, &ScriptEngine::update, this, &ScriptEditorWidget::onScriptModified);
@@ -187,11 +189,12 @@ bool ScriptEditorWidget::save() {
 }
 
 bool ScriptEditorWidget::saveAs() {
+    auto scriptEngines = DependencyManager::get<ScriptEngines>();
     QString fileName = QFileDialog::getSaveFileName(this, tr("Save script"),
-                                                    qApp->getPreviousScriptLocation(),
+                                                    scriptEngines->getPreviousScriptLocation(),
                                                     tr("JavaScript Files (*.js)"));
     if (!fileName.isEmpty()) {
-        qApp->setPreviousScriptLocation(fileName);
+        scriptEngines->setPreviousScriptLocation(fileName);
         return saveFile(fileName);
     } else {
         return false;
diff --git a/interface/src/ui/ScriptEditorWindow.cpp b/interface/src/ui/ScriptEditorWindow.cpp
index 3c6d0f73d5..919c8b64d3 100644
--- a/interface/src/ui/ScriptEditorWindow.cpp
+++ b/interface/src/ui/ScriptEditorWindow.cpp
@@ -16,6 +16,7 @@
 #include "ScriptEditorWidget.h"
 
 #include <QGridLayout>
+#include <QtCore/QSignalMapper>
 #include <QFrame>
 #include <QLayoutItem>
 #include <QMainWindow>
@@ -27,6 +28,7 @@
 #include <QTimer>
 #include <QWidget>
 
+#include <ScriptEngines.h>
 #include "Application.h"
 #include "PathUtils.h"
 
@@ -85,11 +87,12 @@ void ScriptEditorWindow::loadScriptMenu(const QString& scriptName) {
 }
 
 void ScriptEditorWindow::loadScriptClicked() {
+    auto scriptEngines = DependencyManager::get<ScriptEngines>();
     QString scriptName = QFileDialog::getOpenFileName(this, tr("Interface"),
-                                                      qApp->getPreviousScriptLocation(),
+                                                      scriptEngines->getPreviousScriptLocation(),
                                                       tr("JavaScript Files (*.js)"));
     if (!scriptName.isEmpty()) {
-        qApp->setPreviousScriptLocation(scriptName);
+        scriptEngines->setPreviousScriptLocation(scriptName);
         addScriptEditorWidget("loading...")->loadFile(scriptName);
         updateButtons();
     }
@@ -97,7 +100,7 @@ void ScriptEditorWindow::loadScriptClicked() {
 
 void ScriptEditorWindow::loadMenuAboutToShow() {
     _loadMenu->clear();
-    QStringList runningScripts = qApp->getRunningScripts();
+    QStringList runningScripts = DependencyManager::get<ScriptEngines>()->getRunningScripts();;
     if (runningScripts.count() > 0) {
         QSignalMapper* signalMapper = new QSignalMapper(this);
         foreach (const QString& runningScript, runningScripts) {
diff --git a/libraries/script-engine/src/ScriptEngine.cpp b/libraries/script-engine/src/ScriptEngine.cpp
index 8026102478..e997879391 100644
--- a/libraries/script-engine/src/ScriptEngine.cpp
+++ b/libraries/script-engine/src/ScriptEngine.cpp
@@ -46,11 +46,13 @@
 #include "TypedArrays.h"
 #include "XMLHttpRequestClass.h"
 #include "WebSocketClass.h"
-
 #include "RecordingScriptingInterface.h"
+#include "ScriptEngines.h"
 
 #include "MIDIEvent.h"
 
+std::atomic<bool> ScriptEngine::_stoppingAllScripts { false };
+
 static const QString SCRIPT_EXCEPTION_FORMAT = "[UncaughtException] %1 in %2:%3";
 
 Q_DECLARE_METATYPE(QScriptEngine::FunctionSignature)
@@ -132,9 +134,7 @@ ScriptEngine::ScriptEngine(const QString& scriptContents, const QString& fileNam
     _fileNameString(fileNameString),
     _arrayBufferClass(new ArrayBufferClass(this))
 {
-    _allScriptsMutex.lock();
-    _allKnownScriptEngines.insert(this);
-    _allScriptsMutex.unlock();
+    DependencyManager::get<ScriptEngines>()->addScriptEngine(this);
 
     connect(this, &QScriptEngine::signalHandlerException, this, [this](const QScriptValue& exception) {
         hadUncaughtExceptions(*this, _fileNameString);
@@ -144,14 +144,7 @@ ScriptEngine::ScriptEngine(const QString& scriptContents, const QString& fileNam
 ScriptEngine::~ScriptEngine() {
     qCDebug(scriptengine) << "Script Engine shutting down (destructor) for script:" << getFilename();
 
-    // If we're not already in the middle of stopping all scripts, then we should remove ourselves
-    // from the list of running scripts. We don't do this if we're in the process of stopping all scripts
-    // because that method removes scripts from its list as it iterates them
-    if (!_stoppingAllScripts) {
-        _allScriptsMutex.lock();
-        _allKnownScriptEngines.remove(this);
-        _allScriptsMutex.unlock();
-    }
+    DependencyManager::get<ScriptEngines>()->removeScriptEngine(this);
 }
 
 void ScriptEngine::disconnectNonEssentialSignals() {
@@ -187,67 +180,6 @@ void ScriptEngine::runInThread() {
     workerThread->start();
 }
 
-QSet<ScriptEngine*> ScriptEngine::_allKnownScriptEngines;
-QMutex ScriptEngine::_allScriptsMutex;
-std::atomic<bool> ScriptEngine::_stoppingAllScripts { false };
-
-void ScriptEngine::stopAllScripts(QObject* application) {
-    _allScriptsMutex.lock();
-    _stoppingAllScripts = true;
-
-    qCDebug(scriptengine) << "Stopping all scripts.... currently known scripts:" << _allKnownScriptEngines.size();
-
-    QMutableSetIterator<ScriptEngine*> i(_allKnownScriptEngines);
-    while (i.hasNext()) {
-        ScriptEngine* scriptEngine = i.next();
-
-        QString scriptName = scriptEngine->getFilename();
-
-        // NOTE: typically all script engines are running. But there's at least one known exception to this, the
-        // "entities sandbox" which is only used to evaluate entities scripts to test their validity before using
-        // them. We don't need to stop scripts that aren't running.
-        if (scriptEngine->isRunning()) {
-
-            // If the script is running, but still evaluating then we need to wait for its evaluation step to
-            // complete. After that we can handle the stop process appropriately
-            if (scriptEngine->evaluatePending()) {
-                while (scriptEngine->evaluatePending()) {
-
-                    // This event loop allows any started, but not yet finished evaluate() calls to complete
-                    // we need to let these complete so that we can be guaranteed that the script engine isn't
-                    // in a partially setup state, which can confuse our shutdown unwinding.
-                    QEventLoop loop;
-                    QObject::connect(scriptEngine, &ScriptEngine::evaluationFinished, &loop, &QEventLoop::quit);
-                    loop.exec();
-                }
-            }
-
-            // We disconnect any script engine signals from the application because we don't want to do any
-            // extra stopScript/loadScript processing that the Application normally does when scripts start
-            // and stop. We can safely short circuit this because we know we're in the "quitting" process
-            scriptEngine->disconnect(application);
-
-            // Calling stop on the script engine will set it's internal _isFinished state to true, and result
-            // in the ScriptEngine gracefully ending it's run() method.
-            scriptEngine->stop();
-
-            // We need to wait for the engine to be done running before we proceed, because we don't
-            // want any of the scripts final "scriptEnding()" or pending "update()" methods from accessing
-            // any application state after we leave this stopAllScripts() method
-            qCDebug(scriptengine) << "waiting on script:" << scriptName;
-            scriptEngine->waitTillDoneRunning();
-            qCDebug(scriptengine) << "done waiting on script:" << scriptName;
-
-            // If the script is stopped, we can remove it from our set
-            i.remove();
-        }
-    }
-    _stoppingAllScripts = false;
-    _allScriptsMutex.unlock();
-    qCDebug(scriptengine) << "DONE Stopping all scripts....";
-}
-
-
 void ScriptEngine::waitTillDoneRunning() {
     // If the script never started running or finished running before we got here, we don't need to wait for it
     if (_isRunning && _isThreaded) {
diff --git a/libraries/script-engine/src/ScriptEngine.h b/libraries/script-engine/src/ScriptEngine.h
index 67a206d673..f89998d9f0 100644
--- a/libraries/script-engine/src/ScriptEngine.h
+++ b/libraries/script-engine/src/ScriptEngine.h
@@ -129,7 +129,6 @@ public:
     bool isRunning() const { return _isRunning; } // used by ScriptWidget
 
     void disconnectNonEssentialSignals();
-    static void stopAllScripts(QObject* application); // used by Application on shutdown
 
     ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
     // NOTE - These are the callback implementations for ScriptUser the get called by ScriptCache when the contents
@@ -204,8 +203,7 @@ protected:
     void forwardHandlerCall(const EntityItemID& entityID, const QString& eventName, QScriptValueList eventHanderArgs);
     Q_INVOKABLE void entityScriptContentAvailable(const EntityItemID& entityID, const QString& scriptOrURL, const QString& contents, bool isURL, bool success);
 
-    static QSet<ScriptEngine*> _allKnownScriptEngines;
-    static QMutex _allScriptsMutex;
+    friend class ScriptEngines;
     static std::atomic<bool> _stoppingAllScripts;
 };
 
diff --git a/libraries/script-engine/src/ScriptEngines.cpp b/libraries/script-engine/src/ScriptEngines.cpp
new file mode 100644
index 0000000000..a7894f1816
--- /dev/null
+++ b/libraries/script-engine/src/ScriptEngines.cpp
@@ -0,0 +1,434 @@
+//
+//  Created by Bradley Austin Davis on 2016/01/08
+//  Copyright 2013-2016 High Fidelity, Inc.
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+//
+
+#include "ScriptEngines.h"
+
+#include <QtCore/QStandardPaths>
+#include <QtCore/QCoreApplication>
+
+#include <SettingHandle.h>
+#include <UserActivityLogger.h>
+
+#include "ScriptEngine.h"
+#include "ScriptEngineLogging.h"
+
+#define __STR2__(x) #x
+#define __STR1__(x) __STR2__(x)
+#define __LOC__ __FILE__ "("__STR1__(__LINE__)") : Warning Msg: "
+
+#ifndef __APPLE__
+static const QString DESKTOP_LOCATION = QStandardPaths::writableLocation(QStandardPaths::DesktopLocation);
+#else
+// Temporary fix to Qt bug: http://stackoverflow.com/questions/16194475
+static const QString DESKTOP_LOCATION = QStandardPaths::writableLocation(QStandardPaths::DesktopLocation).append("/script.js");
+#endif
+
+ScriptsModel& getScriptsModel() {
+    static ScriptsModel scriptsModel;
+    return scriptsModel;
+}
+
+ScriptEngines::ScriptEngines()
+    : _scriptsLocationHandle("scriptsLocation", DESKTOP_LOCATION),
+      _previousScriptLocation("LastScriptLocation", DESKTOP_LOCATION){
+    _scriptsModelFilter.setSourceModel(&_scriptsModel);
+    _scriptsModelFilter.sort(0, Qt::AscendingOrder);
+    _scriptsModelFilter.setDynamicSortFilter(true);
+}
+
+
+QObject* scriptsModel();
+
+void ScriptEngines::registerScriptInitializer(ScriptInitializer initializer) {
+    _scriptInitializers.push_back(initializer);
+}
+
+void ScriptEngines::addScriptEngine(ScriptEngine* engine) {
+    _allScriptsMutex.lock();
+    _allKnownScriptEngines.insert(engine);
+    _allScriptsMutex.unlock();
+}
+
+void ScriptEngines::removeScriptEngine(ScriptEngine* engine) {
+    // If we're not already in the middle of stopping all scripts, then we should remove ourselves
+    // from the list of running scripts. We don't do this if we're in the process of stopping all scripts
+    // because that method removes scripts from its list as it iterates them
+    if (!_stoppingAllScripts) {
+        _allScriptsMutex.lock();
+        _allKnownScriptEngines.remove(engine);
+        _allScriptsMutex.unlock();
+    }
+}
+
+void ScriptEngines::shutdownScripting() {
+    _allScriptsMutex.lock();
+    _stoppingAllScripts = true;
+    ScriptEngine::_stoppingAllScripts = true;
+    qCDebug(scriptengine) << "Stopping all scripts.... currently known scripts:" << _allKnownScriptEngines.size();
+
+    QMutableSetIterator<ScriptEngine*> i(_allKnownScriptEngines);
+    while (i.hasNext()) {
+        ScriptEngine* scriptEngine = i.next();
+        QString scriptName = scriptEngine->getFilename();
+
+        // NOTE: typically all script engines are running. But there's at least one known exception to this, the
+        // "entities sandbox" which is only used to evaluate entities scripts to test their validity before using
+        // them. We don't need to stop scripts that aren't running.
+        if (scriptEngine->isRunning()) {
+
+            // If the script is running, but still evaluating then we need to wait for its evaluation step to
+            // complete. After that we can handle the stop process appropriately
+            if (scriptEngine->evaluatePending()) {
+                while (scriptEngine->evaluatePending()) {
+
+                    // This event loop allows any started, but not yet finished evaluate() calls to complete
+                    // we need to let these complete so that we can be guaranteed that the script engine isn't
+                    // in a partially setup state, which can confuse our shutdown unwinding.
+                    QEventLoop loop;
+                    QObject::connect(scriptEngine, &ScriptEngine::evaluationFinished, &loop, &QEventLoop::quit);
+                    loop.exec();
+                }
+            }
+
+            // We disconnect any script engine signals from the application because we don't want to do any
+            // extra stopScript/loadScript processing that the Application normally does when scripts start
+            // and stop. We can safely short circuit this because we know we're in the "quitting" process
+            scriptEngine->disconnect(this);
+
+            // Calling stop on the script engine will set it's internal _isFinished state to true, and result
+            // in the ScriptEngine gracefully ending it's run() method.
+            scriptEngine->stop();
+
+            // We need to wait for the engine to be done running before we proceed, because we don't
+            // want any of the scripts final "scriptEnding()" or pending "update()" methods from accessing
+            // any application state after we leave this stopAllScripts() method
+            qCDebug(scriptengine) << "waiting on script:" << scriptName;
+            scriptEngine->waitTillDoneRunning();
+            qCDebug(scriptengine) << "done waiting on script:" << scriptName;
+
+            // If the script is stopped, we can remove it from our set
+            i.remove();
+        }
+    }
+    _stoppingAllScripts = false;
+    _allScriptsMutex.unlock();
+    qCDebug(scriptengine) << "DONE Stopping all scripts....";
+}
+
+QVariantList getPublicChildNodes(TreeNodeFolder* parent) {
+    QVariantList result;
+    QList<TreeNodeBase*> treeNodes = getScriptsModel().getFolderNodes(parent);
+    for (int i = 0; i < treeNodes.size(); i++) {
+        TreeNodeBase* node = treeNodes.at(i);
+        if (node->getType() == TREE_NODE_TYPE_FOLDER) {
+            TreeNodeFolder* folder = static_cast<TreeNodeFolder*>(node);
+            QVariantMap resultNode;
+            resultNode.insert("name", node->getName());
+            resultNode.insert("type", "folder");
+            resultNode.insert("children", getPublicChildNodes(folder));
+            result.append(resultNode);
+            continue;
+        }
+        TreeNodeScript* script = static_cast<TreeNodeScript*>(node);
+        if (script->getOrigin() == ScriptOrigin::SCRIPT_ORIGIN_LOCAL) {
+            continue;
+        }
+        QVariantMap resultNode;
+        resultNode.insert("name", node->getName());
+        resultNode.insert("type", "script");
+        resultNode.insert("url", script->getFullPath());
+        result.append(resultNode);
+    }
+    return result;
+}
+
+QVariantList ScriptEngines::getPublic() {
+    return getPublicChildNodes(NULL);
+}
+
+QVariantList ScriptEngines::getLocal() {
+    QVariantList result;
+    QList<TreeNodeBase*> treeNodes = getScriptsModel().getFolderNodes(NULL);
+    for (int i = 0; i < treeNodes.size(); i++) {
+        TreeNodeBase* node = treeNodes.at(i);
+        if (node->getType() != TREE_NODE_TYPE_SCRIPT) {
+            continue;
+        }
+        TreeNodeScript* script = static_cast<TreeNodeScript*>(node);
+        if (script->getOrigin() != ScriptOrigin::SCRIPT_ORIGIN_LOCAL) {
+            continue;
+        }
+        QVariantMap resultNode;
+        resultNode.insert("name", node->getName());
+        resultNode.insert("path", script->getFullPath());
+        result.append(resultNode);
+    }
+    return result;
+}
+
+QVariantList ScriptEngines::getRunning() {
+    const int WINDOWS_DRIVE_LETTER_SIZE = 1;
+    QVariantList result;
+    auto runningScripts = getRunningScripts();
+    foreach(const QString& runningScript, runningScripts) {
+        QUrl runningScriptURL = QUrl(runningScript);
+        if (runningScriptURL.scheme().size() <= WINDOWS_DRIVE_LETTER_SIZE) {
+            runningScriptURL = QUrl::fromLocalFile(runningScriptURL.toDisplayString(QUrl::FormattingOptions(QUrl::FullyEncoded)));
+        }
+        QVariantMap resultNode;
+        resultNode.insert("name", runningScriptURL.fileName());
+        resultNode.insert("url", runningScriptURL.toDisplayString(QUrl::FormattingOptions(QUrl::FullyEncoded)));
+        // The path contains the exact path/URL of the script, which also is used in the stopScript function.
+        resultNode.insert("path", runningScript);
+        resultNode.insert("local", runningScriptURL.isLocalFile());
+        result.append(resultNode);
+    }
+    return result;
+}
+
+
+static const QString SETTINGS_KEY = "Settings";
+static const QString DEFAULT_SCRIPTS_JS_URL = "http://s3.amazonaws.com/hifi-public/scripts/defaultScripts.js";
+
+void ScriptEngines::loadDefaultScripts() {
+    loadScript(DEFAULT_SCRIPTS_JS_URL);
+}
+
+void ScriptEngines::loadOneScript(const QString& scriptFilename) {
+    loadScript(scriptFilename);
+}
+
+void ScriptEngines::loadScripts() {
+    // check first run...
+    if (_firstRun.get()) {
+        qCDebug(scriptengine) << "This is a first run...";
+        // clear the scripts, and set out script to our default scripts
+        clearScripts();
+        loadDefaultScripts();
+        _firstRun.set(false);
+        return;
+    } 
+
+    // loads all saved scripts
+    Settings settings;
+    int size = settings.beginReadArray(SETTINGS_KEY);
+    for (int i = 0; i < size; ++i) {
+        settings.setArrayIndex(i);
+        QString string = settings.value("script").toString();
+        if (!string.isEmpty()) {
+            loadScript(string);
+        }
+    }
+    settings.endArray();
+}
+
+void ScriptEngines::clearScripts() {
+    // clears all scripts from the settingsSettings settings;
+    Settings settings;
+    settings.beginWriteArray(SETTINGS_KEY);
+    settings.remove("");
+}
+
+void ScriptEngines::saveScripts() {
+    // Saves all currently running user-loaded scripts
+    Settings settings;
+    settings.beginWriteArray(SETTINGS_KEY);
+    settings.remove("");
+
+    QStringList runningScripts = getRunningScripts();
+    int i = 0;
+    for (auto it = runningScripts.begin(); it != runningScripts.end(); ++it) {
+        if (getScriptEngine(*it)->isUserLoaded()) {
+            settings.setArrayIndex(i);
+            settings.setValue("script", *it);
+            ++i;
+        }
+    }
+    settings.endArray();
+}
+
+QStringList ScriptEngines::getRunningScripts() {
+    QReadLocker lock(&_scriptEnginesHashLock);
+    return _scriptEnginesHash.keys();
+}
+
+void ScriptEngines::stopAllScripts(bool restart) {
+    QReadLocker lock(&_scriptEnginesHashLock);
+    if (restart) {
+        // Delete all running scripts from cache so that they are re-downloaded when they are restarted
+        auto scriptCache = DependencyManager::get<ScriptCache>();
+        for (QHash<QString, ScriptEngine*>::const_iterator it = _scriptEnginesHash.constBegin();
+            it != _scriptEnginesHash.constEnd(); it++) {
+            if (!it.value()->isFinished()) {
+                scriptCache->deleteScript(it.key());
+            }
+        }
+    }
+
+    // Stop and possibly restart all currently running scripts
+    for (QHash<QString, ScriptEngine*>::const_iterator it = _scriptEnginesHash.constBegin();
+        it != _scriptEnginesHash.constEnd(); it++) {
+        if (it.value()->isFinished()) {
+            continue;
+        }
+        if (restart && it.value()->isUserLoaded()) {
+            connect(it.value(), &ScriptEngine::finished, this, [this](QString scriptName, ScriptEngine* engine) {
+                reloadScript(scriptName);
+            });
+        }
+        QMetaObject::invokeMethod(it.value(), "stop");
+        //it.value()->stop();
+        qCDebug(scriptengine) << "stopping script..." << it.key();
+    }
+}
+
+bool ScriptEngines::stopScript(const QString& scriptHash, bool restart) {
+    bool stoppedScript = false;
+    {
+        QReadLocker lock(&_scriptEnginesHashLock);
+        if (_scriptEnginesHash.contains(scriptHash)) {
+            ScriptEngine* scriptEngine = _scriptEnginesHash[scriptHash];
+            if (restart) {
+                auto scriptCache = DependencyManager::get<ScriptCache>();
+                scriptCache->deleteScript(QUrl(scriptHash));
+                connect(scriptEngine, &ScriptEngine::finished, this, [this](QString scriptName, ScriptEngine* engine) {
+                    reloadScript(scriptName);
+                });
+            }
+            scriptEngine->stop();
+            stoppedScript = true;
+            qCDebug(scriptengine) << "stopping script..." << scriptHash;
+        }
+    }
+    return stoppedScript;
+}
+
+QString ScriptEngines::getScriptsLocation() const {
+    return _scriptsLocationHandle.get();
+}
+
+void ScriptEngines::setScriptsLocation(const QString& scriptsLocation) {
+    _scriptsLocationHandle.set(scriptsLocation);
+    _scriptsModel.updateScriptsLocation(scriptsLocation);
+}
+
+void ScriptEngines::reloadAllScripts() { 
+    DependencyManager::get<ScriptCache>()->clearCache();
+    emit scriptsReloading();
+    stopAllScripts(true);
+}
+
+ScriptEngine* ScriptEngines::loadScript(const QString& scriptFilename, bool isUserLoaded, bool loadScriptFromEditor, bool activateMainWindow, bool reload) {
+    if (thread() != QThread::currentThread()) {
+        ScriptEngine* result { nullptr };
+        QMetaObject::invokeMethod(this, "loadScript", Qt::BlockingQueuedConnection, Q_RETURN_ARG(ScriptEngine*, result),
+            Q_ARG(QString, scriptFilename),
+            Q_ARG(bool, isUserLoaded),
+            Q_ARG(bool, loadScriptFromEditor),
+            Q_ARG(bool, activateMainWindow),
+            Q_ARG(bool, reload));
+        return result;
+    }
+    QUrl scriptUrl(scriptFilename);
+    auto scriptEngine = getScriptEngine(scriptUrl.toString());
+    if (scriptEngine) {
+        return scriptEngine;
+    }
+
+    scriptEngine = new ScriptEngine(NO_SCRIPT, "", true);
+    scriptEngine->setUserLoaded(isUserLoaded);
+
+    if (scriptFilename.isNull()) {
+        launchScriptEngine(scriptEngine);
+    } else {
+        // connect to the appropriate signals of this script engine
+        connect(scriptEngine, &ScriptEngine::scriptLoaded, this, &ScriptEngines::onScriptEngineLoaded);
+        connect(scriptEngine, &ScriptEngine::errorLoadingScript, this, &ScriptEngines::onScriptEngineError);
+
+        // get the script engine object to load the script at the designated script URL
+        scriptEngine->loadURL(scriptUrl, reload);
+    }
+
+    return scriptEngine;
+}
+
+ScriptEngine* ScriptEngines::getScriptEngine(const QString& scriptHash) {
+    ScriptEngine* result = nullptr;
+    {
+        QReadLocker lock(&_scriptEnginesHashLock);
+        auto it = _scriptEnginesHash.find(scriptHash);
+        if (it != _scriptEnginesHash.end()) {
+            result = it.value();
+        }
+    }
+    return result;
+}
+
+// FIXME - change to new version of ScriptCache loading notification
+void ScriptEngines::onScriptEngineLoaded(const QString& scriptFilename) {
+    UserActivityLogger::getInstance().loadedScript(scriptFilename);
+    ScriptEngine* scriptEngine = qobject_cast<ScriptEngine*>(sender());
+
+    launchScriptEngine(scriptEngine);
+
+    {
+        QWriteLocker lock(&_scriptEnginesHashLock);
+        _scriptEnginesHash.insertMulti(scriptFilename, scriptEngine);
+    }
+    emit scriptCountChanged();
+}
+
+void ScriptEngines::launchScriptEngine(ScriptEngine* scriptEngine) {
+    connect(scriptEngine, &ScriptEngine::finished, this, &ScriptEngines::onScriptFinished, Qt::DirectConnection);
+    connect(scriptEngine, &ScriptEngine::loadScript, [&](const QString& scriptName, bool userLoaded) {
+        loadScript(scriptName, userLoaded);
+    });
+    connect(scriptEngine, &ScriptEngine::reloadScript, [&](const QString& scriptName, bool userLoaded) {
+        loadScript(scriptName, userLoaded, false, false, true);
+    });
+
+    // register our application services and set it off on its own thread
+    for (auto initializer : _scriptInitializers) {
+        initializer(scriptEngine);
+    }
+    scriptEngine->runInThread();
+}
+
+
+void ScriptEngines::onScriptFinished(const QString& scriptName, ScriptEngine* engine) {
+    bool removed = false;
+    {
+        QWriteLocker lock(&_scriptEnginesHashLock);
+        const QString& scriptURLString = QUrl(scriptName).toString();
+        for (auto it = _scriptEnginesHash.find(scriptURLString); it != _scriptEnginesHash.end(); ++it) {
+            if (it.value() == engine) {
+                _scriptEnginesHash.erase(it);
+                removed = true;
+                break;
+            }
+        }
+    }
+
+    if (removed) {
+        emit scriptCountChanged();
+    }
+}
+
+// FIXME - change to new version of ScriptCache loading notification
+void ScriptEngines::onScriptEngineError(const QString& scriptFilename) {
+    qCDebug(scriptengine) << "Application::loadScript(), script failed to load...";
+    emit scriptLoadError(scriptFilename, "");
+}
+
+QString ScriptEngines::getPreviousScriptLocation() const {
+    return _previousScriptLocation.get();
+}
+
+void ScriptEngines::setPreviousScriptLocation(const QString& previousScriptLocation) {
+    _previousScriptLocation.set(previousScriptLocation);
+}
diff --git a/libraries/script-engine/src/ScriptEngines.h b/libraries/script-engine/src/ScriptEngines.h
new file mode 100644
index 0000000000..6d78f3cfa0
--- /dev/null
+++ b/libraries/script-engine/src/ScriptEngines.h
@@ -0,0 +1,103 @@
+//
+//  Created by Bradley Austin Davis on 2016/01/08
+//  Copyright 2013-2016 High Fidelity, Inc.
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+//
+
+#ifndef hifi_ScriptEngines_h
+#define hifi_ScriptEngines_h
+
+#include <functional>
+#include <atomic>
+#include <memory>
+
+#include <QtCore/QObject>
+#include <QtCore/QMutex>
+#include <QtCore/QReadWriteLock>
+
+#include <SettingHandle.h>
+#include <DependencyManager.h>
+
+#include "ScriptsModel.h"
+#include "ScriptsModelFilter.h"
+
+class ScriptEngine;
+
+class ScriptEngines : public QObject, public Dependency {
+    Q_OBJECT
+
+    Q_PROPERTY(ScriptsModel* scriptsModel READ scriptsModel CONSTANT)
+    Q_PROPERTY(ScriptsModelFilter* scriptsModelFilter READ scriptsModelFilter CONSTANT)
+
+public:
+    using ScriptInitializer = std::function<void(ScriptEngine*)>;
+
+    ScriptEngines();
+    void registerScriptInitializer(ScriptInitializer initializer);
+
+    void loadScripts();
+    void saveScripts();
+    void clearScripts();
+
+    QString getScriptsLocation() const;
+    void loadDefaultScripts();
+    void setScriptsLocation(const QString& scriptsLocation);
+    QStringList getRunningScripts();
+    ScriptEngine* getScriptEngine(const QString& scriptHash);
+
+    QString getPreviousScriptLocation() const;
+    void setPreviousScriptLocation(const QString& previousScriptLocation);
+
+    ScriptsModel* scriptsModel() { return &_scriptsModel; };
+    ScriptsModelFilter* scriptsModelFilter() { return &_scriptsModelFilter; };
+
+    Q_INVOKABLE void loadOneScript(const QString& scriptFilename);
+    Q_INVOKABLE ScriptEngine* loadScript(const QString& scriptFilename = QString(),
+        bool isUserLoaded = true, bool loadScriptFromEditor = false, bool activateMainWindow = false, bool reload = false);
+    Q_INVOKABLE bool stopScript(const QString& scriptHash, bool restart = false);
+
+    Q_INVOKABLE void reloadAllScripts();
+    Q_INVOKABLE void stopAllScripts(bool restart = false);
+
+    Q_INVOKABLE QVariantList getRunning();
+    Q_INVOKABLE QVariantList getPublic();
+    Q_INVOKABLE QVariantList getLocal();
+
+    // Called at shutdown time
+    void shutdownScripting();
+
+signals: 
+    void scriptCountChanged();
+    void scriptsReloading();
+    void scriptLoadError(const QString& filename, const QString& error);
+
+protected slots: 
+    void onScriptFinished(const QString& fileNameString, ScriptEngine* engine);
+
+protected:
+    friend class ScriptEngine;
+
+    void reloadScript(const QString& scriptName) { loadScript(scriptName, true, false, false, true); }
+    void addScriptEngine(ScriptEngine* engine);
+    void removeScriptEngine(ScriptEngine* engine);
+    void onScriptEngineLoaded(const QString& scriptFilename);
+    void onScriptEngineError(const QString& scriptFilename);
+    void launchScriptEngine(ScriptEngine* engine);
+
+
+    Setting::Handle<bool> _firstRun { "firstRun", true };
+    QReadWriteLock _scriptEnginesHashLock;
+    QHash<QString, ScriptEngine*> _scriptEnginesHash;
+    QSet<ScriptEngine*> _allKnownScriptEngines;
+    QMutex _allScriptsMutex;
+    std::atomic<bool> _stoppingAllScripts { false };
+    std::list<ScriptInitializer> _scriptInitializers;
+    mutable Setting::Handle<QString> _scriptsLocationHandle;
+    mutable Setting::Handle<QString> _previousScriptLocation;
+    ScriptsModel _scriptsModel;
+    ScriptsModelFilter _scriptsModelFilter;
+};
+
+#endif // hifi_ScriptEngine_h
diff --git a/interface/src/ScriptsModel.cpp b/libraries/script-engine/src/ScriptsModel.cpp
similarity index 96%
rename from interface/src/ScriptsModel.cpp
rename to libraries/script-engine/src/ScriptsModel.cpp
index a59d499863..07518dded1 100644
--- a/interface/src/ScriptsModel.cpp
+++ b/libraries/script-engine/src/ScriptsModel.cpp
@@ -1,7 +1,4 @@
 //
-//  ScriptsModel.cpp
-//  interface/src
-//
 //  Created by Ryan Huffman on 05/12/14.
 //  Copyright 2014 High Fidelity, Inc.
 //
@@ -11,17 +8,21 @@
 //  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
 //
 
+#include "ScriptsModel.h"
+
 #include <QUrl>
 #include <QUrlQuery>
 #include <QXmlStreamReader>
 
 #include <NetworkAccessManager.h>
 
-#include "Application.h"
-#include "Menu.h"
-#include "InterfaceLogging.h"
+#include "ScriptEngine.h"
+#include "ScriptEngines.h"
+#include "ScriptEngineLogging.h"
+#define __STR2__(x) #x
+#define __STR1__(x) __STR2__(x)
+#define __LOC__ __FILE__ "("__STR1__(__LINE__)") : Warning Msg: "
 
-#include "ScriptsModel.h"
 
 static const QString S3_URL = "http://s3.amazonaws.com/hifi-public";
 static const QString PUBLIC_URL = "http://public.highfidelity.io";
@@ -60,11 +61,8 @@ ScriptsModel::ScriptsModel(QObject* parent) :
     _localDirectory.setFilter(QDir::Files | QDir::Readable);
     _localDirectory.setNameFilters(QStringList("*.js"));
 
-    updateScriptsLocation(qApp->getScriptsLocation());
-    
+    auto scriptEngines = DependencyManager::get<ScriptEngines>();
     connect(&_fsWatcher, &QFileSystemWatcher::directoryChanged, this, &ScriptsModel::reloadLocalFiles);
-    connect(qApp, &Application::scriptLocationChanged, this, &ScriptsModel::updateScriptsLocation);
-
     reloadLocalFiles();
     reloadRemoteFiles();
 }
@@ -182,7 +180,7 @@ void ScriptsModel::downloadFinished() {
         if (!data.isEmpty()) {
             finished = parseXML(data);
         } else {
-            qCDebug(interfaceapp) << "Error: Received no data when loading remote scripts";
+            qCDebug(scriptengine) << "Error: Received no data when loading remote scripts";
         }
     }
 
@@ -231,7 +229,7 @@ bool ScriptsModel::parseXML(QByteArray xmlFile) {
 
     // Error handling
     if (xml.hasError()) {
-        qCDebug(interfaceapp) << "Error loading remote scripts: " << xml.errorString();
+        qCDebug(scriptengine) << "Error loading remote scripts: " << xml.errorString();
         return true;
     }
 
diff --git a/interface/src/ScriptsModel.h b/libraries/script-engine/src/ScriptsModel.h
similarity index 98%
rename from interface/src/ScriptsModel.h
rename to libraries/script-engine/src/ScriptsModel.h
index ae75acfa3b..df9716d43b 100644
--- a/interface/src/ScriptsModel.h
+++ b/libraries/script-engine/src/ScriptsModel.h
@@ -92,6 +92,7 @@ protected:
     void rebuildTree();
 
 private:
+    friend class ScriptEngines;
     bool _loadingScripts;
     QDir _localDirectory;
     QFileSystemWatcher _fsWatcher;
diff --git a/interface/src/ScriptsModelFilter.cpp b/libraries/script-engine/src/ScriptsModelFilter.cpp
similarity index 100%
rename from interface/src/ScriptsModelFilter.cpp
rename to libraries/script-engine/src/ScriptsModelFilter.cpp
diff --git a/interface/src/ScriptsModelFilter.h b/libraries/script-engine/src/ScriptsModelFilter.h
similarity index 100%
rename from interface/src/ScriptsModelFilter.h
rename to libraries/script-engine/src/ScriptsModelFilter.h