diff --git a/examples/edit.js b/examples/edit.js
index 92e4737f29..23cc942192 100644
--- a/examples/edit.js
+++ b/examples/edit.js
@@ -1321,6 +1321,15 @@ PropertiesTool = function(opts) {
                     pushCommandForSelections();
                     selectionManager._update();
                 }
+            } else if (data.action == "reloadScript") {
+                if (selectionManager.hasSelection()) {
+                    var timestamp = Date.now();
+                    for (var i = 0; i < selectionManager.selections.length; i++) {
+                        Entities.editEntity(selectionManager.selections[i], {
+                            scriptTimestamp: timestamp,
+                        });
+                    }
+                }
             } else if (data.action == "centerAtmosphereToZone") {
                 if (selectionManager.hasSelection()) {
                     selectionManager.saveProperties();
diff --git a/examples/html/entityProperties.html b/examples/html/entityProperties.html
index c974845585..8a15147f16 100644
--- a/examples/html/entityProperties.html
+++ b/examples/html/entityProperties.html
@@ -250,6 +250,8 @@
             var elCollisionSoundURL = document.getElementById("property-collision-sound-url");
             var elLifetime = document.getElementById("property-lifetime");
             var elScriptURL = document.getElementById("property-script-url");
+            var elScriptTimestamp = document.getElementById("property-script-timestamp");
+            var elReloadScriptButton = document.getElementById("reload-script-button");
             var elUserData = document.getElementById("property-user-data");
 
             var elColorSection = document.getElementById("color-section");
@@ -470,6 +472,7 @@
                             elCollisionSoundURL.value = properties.collisionSoundURL;
                             elLifetime.value = properties.lifetime;
                             elScriptURL.value = properties.script;
+                            elScriptTimestamp.value = properties.scriptTimestamp;
                             elUserData.value = properties.userData;
 
                             elHyperlinkHref.value = properties.href;
@@ -688,6 +691,7 @@
 
             elLifetime.addEventListener('change', createEmitNumberPropertyUpdateFunction('lifetime'));
             elScriptURL.addEventListener('change', createEmitTextPropertyUpdateFunction('script'));
+            elScriptTimestamp.addEventListener('change', createEmitNumberPropertyUpdateFunction('scriptTimestamp'));
             elUserData.addEventListener('change', createEmitTextPropertyUpdateFunction('userData'));
 
             var colorChangeFunction = createEmitColorPropertyUpdateFunction(
@@ -889,6 +893,12 @@
                     percentage: parseInt(elRescaleDimensionsPct.value),
                 }));
             });
+            elReloadScriptButton.addEventListener("click", function() {
+                EventBridge.emitWebEvent(JSON.stringify({
+                    type: "action",
+                    action: "reloadScript"
+                }));
+            });
             elCenterAtmosphereToZone.addEventListener("click", function() {
                 EventBridge.emitWebEvent(JSON.stringify({
                     type: "action",
@@ -1181,7 +1191,10 @@
         </div>
 
         <div class="property">
-            <div class="label">Script URL</div>
+            <div class="label">Script URL
+                <input type="hidden" id="property-script-timestamp" class="value"></input>
+                <input type="button" id="reload-script-button" value="Reload"></input>
+            </div>
             <div class="value">
                 <input id="property-script-url" class="url"></input>
             </div>
diff --git a/examples/html/style.css b/examples/html/style.css
index f12cfb6dd0..e63b6338fc 100644
--- a/examples/html/style.css
+++ b/examples/html/style.css
@@ -260,6 +260,11 @@ table#properties-list {
     height: 1.2em;
 }
 
+#properties-list .label input[type=button] {
+    float: right;
+    padding: 0 5px 1px;
+}
+
 #properties-list .value > div{
     padding: 3pt 0;
 }
diff --git a/interface/resources/images/reload-script.svg b/interface/resources/images/reload-script.svg
new file mode 100644
index 0000000000..a33de448dc
--- /dev/null
+++ b/interface/resources/images/reload-script.svg
@@ -0,0 +1,50 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   version="1.1"
+   x="0px"
+   y="0px"
+   viewBox="0 0 100 100"
+   enable-background="new 0 0 100 100"
+   xml:space="preserve"
+   id="svg2"
+   inkscape:version="0.91 r13725"
+   sodipodi:docname="reload-script-43339.svg"><metadata
+     id="metadata14"><rdf:RDF><cc:Work
+         rdf:about=""><dc:format>image/svg+xml</dc:format><dc:type
+           rdf:resource="http://purl.org/dc/dcmitype/StillImage" /></cc:Work></rdf:RDF></metadata><defs
+     id="defs12" /><sodipodi:namedview
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1"
+     objecttolerance="10"
+     gridtolerance="10"
+     guidetolerance="10"
+     inkscape:pageopacity="0"
+     inkscape:pageshadow="2"
+     inkscape:window-width="1184"
+     inkscape:window-height="655"
+     id="namedview10"
+     showgrid="false"
+     inkscape:zoom="2.36"
+     inkscape:cx="-12.5"
+     inkscape:cy="56.355932"
+     inkscape:window-x="424"
+     inkscape:window-y="79"
+     inkscape:window-maximized="0"
+     inkscape:current-layer="svg2" /><g
+     id="g4"
+     style="fill:#c4c4c4;fill-opacity:1"
+     transform="matrix(1.0520186,0,0,1.0809642,-4.9561957,-7.0141066)"><g
+       id="g6"
+       style="fill:#c4c4c4;fill-opacity:1"><path
+         d="m 8.139,47.902 14.505,0 c 1.51,0 2.838,-0.987 3.28,-2.429 1.222,-4.042 3.425,-7.649 6.357,-10.583 4.643,-4.627 10.918,-7.442 17.982,-7.45 7.056,0.008 13.331,2.823 17.979,7.45 0.144,0.147 0.271,0.31 0.411,0.457 L 59.46,46.155 c -0.257,0.299 -0.313,0.724 -0.157,1.078 0.173,0.365 0.53,0.59 0.923,0.584 l 38.526,0.111 c 0.294,0.005 0.581,-0.129 0.771,-0.352 0.197,-0.231 0.278,-0.527 0.23,-0.818 L 93.483,8.741 C 93.421,8.353 93.137,8.038 92.753,7.933 92.375,7.828 91.968,7.952 91.714,8.248 L 82.256,19.366 C 73.983,11.441 62.706,6.512 50.337,6.491 50.279,6.488 50.206,6.488 50.122,6.491 37.396,6.527 25.801,11.73 17.469,20.08 11.119,26.417 6.604,34.634 4.776,43.81 c -0.198,1.013 0.062,2.046 0.715,2.843 0.655,0.793 1.617,1.249 2.648,1.249 z m 90.845,10.939 c -0.652,-0.798 -1.618,-1.259 -2.646,-1.259 l -14.506,0 c -1.507,0 -2.836,0.991 -3.279,2.435 -1.223,4.039 -3.427,7.649 -6.357,10.587 -4.64,4.622 -10.915,7.439 -17.982,7.45 -7.056,-0.011 -13.331,-2.828 -17.979,-7.45 -0.144,-0.146 -0.269,-0.32 -0.41,-0.464 l 9.196,-10.811 c 0.256,-0.294 0.311,-0.717 0.154,-1.076 -0.173,-0.356 -0.527,-0.587 -0.923,-0.585 L 5.727,57.561 c -0.294,0 -0.581,0.126 -0.773,0.352 -0.195,0.229 -0.277,0.524 -0.229,0.824 l 6.271,38.012 c 0.062,0.388 0.345,0.701 0.729,0.812 0.378,0.104 0.784,-0.025 1.039,-0.322 L 22.22,86.125 c 8.278,7.922 19.553,12.859 31.921,12.87 0.06,0.005 0.131,0.005 0.215,0 12.729,-0.032 24.323,-5.237 32.655,-13.583 6.348,-6.338 10.865,-14.561 12.69,-23.728 0.199,-1.012 -0.062,-2.045 -0.717,-2.843 z"
+         id="path8"
+         style="fill:#c4c4c4;fill-opacity:1"
+         inkscape:connector-curvature="0" /></g></g></svg>
\ No newline at end of file
diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index d9c5589631..eb6a53f765 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -4048,6 +4048,7 @@ void Application::registerScriptEngineWithApplicationServices(ScriptEngine* scri
     connect(scriptEngine, SIGNAL(finished(const QString&)), this, SLOT(scriptFinished(const QString&)));
 
     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);
@@ -4263,7 +4264,7 @@ bool Application::askToLoadScript(const QString& scriptFilenameOrURL) {
 }
 
 ScriptEngine* Application::loadScript(const QString& scriptFilename, bool isUserLoaded,
-                                        bool loadScriptFromEditor, bool activateMainWindow) {
+                                        bool loadScriptFromEditor, bool activateMainWindow, bool reload) {
 
     if (isAboutToQuit()) {
         return NULL;
@@ -4292,7 +4293,7 @@ ScriptEngine* Application::loadScript(const QString& scriptFilename, bool isUser
         connect(scriptEngine, &ScriptEngine::errorLoadingScript, this, &Application::handleScriptLoadError);
 
         // get the script engine object to load the script at the designated script URL
-        scriptEngine->loadURL(scriptUrl);
+        scriptEngine->loadURL(scriptUrl, reload);
     }
 
     // restore the main window's active state
@@ -4303,6 +4304,10 @@ ScriptEngine* Application::loadScript(const QString& scriptFilename, bool isUser
     return scriptEngine;
 }
 
+void Application::reloadScript(const QString& scriptName, bool isUserLoaded) {
+    loadScript(scriptName, isUserLoaded, false, false, true);
+}
+
 void Application::handleScriptEngineLoaded(const QString& scriptFilename) {
     ScriptEngine* scriptEngine = qobject_cast<ScriptEngine*>(sender());
 
@@ -4330,14 +4335,25 @@ void Application::scriptFinished(const QString& scriptName) {
 }
 
 void Application::stopAllScripts(bool restart) {
-    // stops all current running scripts
+    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(), SIGNAL(finished(const QString&)), SLOT(loadScript(const QString&)));
+            connect(it.value(), SIGNAL(finished(const QString&)), SLOT(reloadScript(const QString&)));
         }
         it.value()->stop();
         qCDebug(interfaceapp) << "stopping script..." << it.key();
@@ -4345,13 +4361,20 @@ void Application::stopAllScripts(bool restart) {
     // HACK: ATM scripts cannot set/get their animation priorities, so we clear priorities
     // whenever a script stops in case it happened to have been setting joint rotations.
     // TODO: expose animation priorities and provide a layered animation control system.
+    _myAvatar->clearJointAnimationPriorities();
     _myAvatar->clearScriptableSettings();
 }
 
-void Application::stopScript(const QString &scriptName) {
+void Application::stopScript(const QString &scriptName, bool restart) {
     const QString& scriptURLString = QUrl(scriptName).toString();
     if (_scriptEnginesHash.contains(scriptURLString)) {
-        _scriptEnginesHash.value(scriptURLString)->stop();
+        ScriptEngine* scriptEngine = _scriptEnginesHash[scriptURLString];
+        if (restart) {
+            auto scriptCache = DependencyManager::get<ScriptCache>();
+            scriptCache->deleteScript(scriptName);
+            connect(scriptEngine, SIGNAL(finished(const QString&)), SLOT(reloadScript(const QString&)));
+        }
+        scriptEngine->stop();
         qCDebug(interfaceapp) << "stopping script..." << scriptName;
         // HACK: ATM scripts cannot set/get their animation priorities, so we clear priorities
         // whenever a script stops in case it happened to have been setting joint rotations.
@@ -4367,6 +4390,10 @@ void Application::reloadAllScripts() {
     stopAllScripts(true);
 }
 
+void Application::reloadOneScript(const QString& scriptName) {
+    stopScript(scriptName, true);
+}
+
 void Application::loadDefaultScripts() {
     if (!_scriptEnginesHash.contains(DEFAULT_SCRIPTS_JS_URL)) {
         loadScript(DEFAULT_SCRIPTS_JS_URL);
diff --git a/interface/src/Application.h b/interface/src/Application.h
index 2c78327f02..0787cffbdc 100644
--- a/interface/src/Application.h
+++ b/interface/src/Application.h
@@ -409,15 +409,19 @@ public slots:
     bool acceptSnapshot(const QString& urlString);
     bool askToSetAvatarUrl(const QString& url);
     bool askToLoadScript(const QString& scriptFilenameOrURL);
+
     ScriptEngine* loadScript(const QString& scriptFilename = QString(), bool isUserLoaded = true, 
-        bool loadScriptFromEditor = false, bool activateMainWindow = false);
+        bool loadScriptFromEditor = false, bool activateMainWindow = false, bool reload = false);
+    void reloadScript(const QString& scriptName, bool isUserLoaded = true);
     void scriptFinished(const QString& scriptName);
     void stopAllScripts(bool restart = false);
-    void stopScript(const QString& scriptName);
+    void stopScript(const QString& scriptName, bool restart = false);
     void reloadAllScripts();
+    void reloadOneScript(const QString& scriptName);
     void loadDefaultScripts();
     void toggleRunningScriptsWidget();
     void saveScripts();
+
     void showFriendsWindow();
     void friendsWindowClosed();
 
diff --git a/interface/src/ui/RunningScriptsWidget.cpp b/interface/src/ui/RunningScriptsWidget.cpp
index 31c9271c22..1165de7592 100644
--- a/interface/src/ui/RunningScriptsWidget.cpp
+++ b/interface/src/ui/RunningScriptsWidget.cpp
@@ -32,7 +32,8 @@ RunningScriptsWidget::RunningScriptsWidget(QWidget* parent) :
     QWidget(parent, Qt::Window | Qt::CustomizeWindowHint | Qt::WindowTitleHint | Qt::WindowMinMaxButtonsHint |
             Qt::WindowCloseButtonHint),
     ui(new Ui::RunningScriptsWidget),
-    _signalMapper(this),
+    _reloadSignalMapper(this),
+    _stopSignalMapper(this),
     _scriptsModelFilter(this),
     _scriptsModel(this) {
     ui->setupUi(this);
@@ -64,7 +65,8 @@ RunningScriptsWidget::RunningScriptsWidget(QWidget* parent) :
             Application::getInstance(), &Application::loadDialog);
     connect(ui->loadScriptFromURLButton, &QPushButton::clicked,
             Application::getInstance(), &Application::loadScriptURLDialog);
-    connect(&_signalMapper, SIGNAL(mapped(QString)), Application::getInstance(), SLOT(stopScript(const QString&)));
+    connect(&_reloadSignalMapper, SIGNAL(mapped(QString)), Application::getInstance(), SLOT(reloadOneScript(const QString&)));
+    connect(&_stopSignalMapper, SIGNAL(mapped(QString)), Application::getInstance(), SLOT(stopScript(const QString&)));
 
     UIUtil::scaleWidgetFontSizes(this);
 }
@@ -115,6 +117,17 @@ void RunningScriptsWidget::setRunningScripts(const QStringList& list) {
             name->setText(name->text() + "(" + QString::number(hash.find(list.at(i)).value()) + ")");
         }
         ++hash[list.at(i)];
+
+        QPushButton* reloadButton = new QPushButton(row);
+        reloadButton->setFlat(true);
+        reloadButton->setIcon(
+            QIcon(QPixmap(PathUtils::resourcesPath() + "images/reload-script.svg").scaledToHeight(CLOSE_ICON_HEIGHT)));
+        reloadButton->setSizePolicy(QSizePolicy(QSizePolicy::Maximum, QSizePolicy::Preferred));
+        reloadButton->setStyleSheet("border: 0;");
+        reloadButton->setCursor(Qt::PointingHandCursor);
+        connect(reloadButton, SIGNAL(clicked()), &_reloadSignalMapper, SLOT(map()));
+        _reloadSignalMapper.setMapping(reloadButton, url.toString());
+
         QPushButton* closeButton = new QPushButton(row);
         closeButton->setFlat(true);
         closeButton->setIcon(
@@ -122,9 +135,8 @@ void RunningScriptsWidget::setRunningScripts(const QStringList& list) {
         closeButton->setSizePolicy(QSizePolicy(QSizePolicy::Maximum, QSizePolicy::Preferred));
         closeButton->setStyleSheet("border: 0;");
         closeButton->setCursor(Qt::PointingHandCursor);
-
-        connect(closeButton, SIGNAL(clicked()), &_signalMapper, SLOT(map()));
-        _signalMapper.setMapping(closeButton, url.toString());
+        connect(closeButton, SIGNAL(clicked()), &_stopSignalMapper, SLOT(map()));
+        _stopSignalMapper.setMapping(closeButton, url.toString());
 
         row->setSizePolicy(QSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed));
 
@@ -132,6 +144,7 @@ void RunningScriptsWidget::setRunningScripts(const QStringList& list) {
         row->layout()->setSpacing(0);
 
         row->layout()->addWidget(name);
+        row->layout()->addWidget(reloadButton);
         row->layout()->addWidget(closeButton);
 
         row->setToolTip(url.toString());
diff --git a/interface/src/ui/RunningScriptsWidget.h b/interface/src/ui/RunningScriptsWidget.h
index 5d3f6843af..c09bce5443 100644
--- a/interface/src/ui/RunningScriptsWidget.h
+++ b/interface/src/ui/RunningScriptsWidget.h
@@ -36,7 +36,7 @@ public:
     const ScriptsModel* getScriptsModel() { return &_scriptsModel; }
 
 signals:
-    void stopScriptName(const QString& name);
+    void stopScriptName(const QString& name, bool restart = false);
 
 protected:
     virtual bool eventFilter(QObject* sender, QEvent* event);
@@ -59,7 +59,8 @@ private slots:
 
 private:
     Ui::RunningScriptsWidget* ui;
-    QSignalMapper _signalMapper;
+    QSignalMapper _reloadSignalMapper;
+    QSignalMapper _stopSignalMapper;
     ScriptsModelFilter _scriptsModelFilter;
     ScriptsModel _scriptsModel;
     ScriptsTableWidget* _recentlyLoadedScriptsTable;
diff --git a/libraries/entities-renderer/src/EntityTreeRenderer.cpp b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
index 0ea6080165..03d88200c5 100644
--- a/libraries/entities-renderer/src/EntityTreeRenderer.cpp
+++ b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
@@ -122,9 +122,9 @@ void EntityTreeRenderer::init() {
     // first chance, we'll check for enter/leave entity events.    
     _lastAvatarPosition = _viewState->getAvatarPosition() + glm::vec3((float)TREE_SCALE);
     
-    connect(entityTree, &EntityTree::deletingEntity, this, &EntityTreeRenderer::deletingEntity);
-    connect(entityTree, &EntityTree::addingEntity, this, &EntityTreeRenderer::addingEntity);
-    connect(entityTree, &EntityTree::entityScriptChanging, this, &EntityTreeRenderer::entitySciptChanging);
+    connect(entityTree, &EntityTree::deletingEntity, this, &EntityTreeRenderer::deletingEntity, Qt::QueuedConnection);
+    connect(entityTree, &EntityTree::addingEntity, this, &EntityTreeRenderer::addingEntity, Qt::QueuedConnection);
+    connect(entityTree, &EntityTree::entityScriptChanging, this, &EntityTreeRenderer::entitySciptChanging, Qt::QueuedConnection);
 }
 
 void EntityTreeRenderer::shutdown() {
@@ -148,13 +148,14 @@ void EntityTreeRenderer::errorInLoadingScript(const QUrl& url) {
     }
 }
 
-QScriptValue EntityTreeRenderer::loadEntityScript(const EntityItemID& entityItemID, bool isPreload) {
+QScriptValue EntityTreeRenderer::loadEntityScript(const EntityItemID& entityItemID, bool isPreload, bool reload) {
     EntityItemPointer entity = static_cast<EntityTree*>(_tree)->findEntityByEntityItemID(entityItemID);
-    return loadEntityScript(entity, isPreload);
+    return loadEntityScript(entity, isPreload, reload);
 }
 
 
-QString EntityTreeRenderer::loadScriptContents(const QString& scriptMaybeURLorText, bool& isURL, bool& isPending, QUrl& urlOut) {
+QString EntityTreeRenderer::loadScriptContents(const QString& scriptMaybeURLorText, bool& isURL, bool& isPending, QUrl& urlOut, 
+        bool& reload) {
     isPending = false;
     QUrl url(scriptMaybeURLorText);
     
@@ -192,7 +193,7 @@ QString EntityTreeRenderer::loadScriptContents(const QString& scriptMaybeURLorTe
             auto scriptCache = DependencyManager::get<ScriptCache>();
             
             if (!scriptCache->isInBadScriptList(url)) {
-                scriptContents = scriptCache->getScript(url, this, isPending);
+                scriptContents = scriptCache->getScript(url, this, isPending, reload);
             }
         }
     }
@@ -201,7 +202,7 @@ QString EntityTreeRenderer::loadScriptContents(const QString& scriptMaybeURLorTe
 }
 
 
-QScriptValue EntityTreeRenderer::loadEntityScript(EntityItemPointer entity, bool isPreload) {
+QScriptValue EntityTreeRenderer::loadEntityScript(EntityItemPointer entity, bool isPreload, bool reload) {
     if (_shuttingDown) {
         return QScriptValue(); // since we're shutting down, we don't load any more scripts
     }
@@ -221,8 +222,8 @@ QScriptValue EntityTreeRenderer::loadEntityScript(EntityItemPointer entity, bool
     if (_entityScripts.contains(entityID)) {
         EntityScriptDetails details = _entityScripts[entityID];
         
-        // check to make sure our script text hasn't changed on us since we last loaded it
-        if (details.scriptText == entityScript) {
+        // check to make sure our script text hasn't changed on us since we last loaded it and we're not redownloading it
+        if (details.scriptText == entityScript && !reload) {
             return details.scriptObject; // previously loaded
         }
         
@@ -237,7 +238,7 @@ QScriptValue EntityTreeRenderer::loadEntityScript(EntityItemPointer entity, bool
     bool isURL = false; // loadScriptContents() will tell us if this is a URL or just text.
     bool isPending = false;
     QUrl url;
-    QString scriptContents = loadScriptContents(entityScript, isURL, isPending, url);
+    QString scriptContents = loadScriptContents(entityScript, isURL, isPending, url, reload);
     
     if (isPending && isPreload && isURL) {
         _waitingOnPreload.insert(url, entityID);
@@ -1030,17 +1031,17 @@ void EntityTreeRenderer::addEntityToScene(EntityItemPointer entity) {
 }
 
 
-void EntityTreeRenderer::entitySciptChanging(const EntityItemID& entityID) {
+void EntityTreeRenderer::entitySciptChanging(const EntityItemID& entityID, const bool reload) {
     if (_tree && !_shuttingDown) {
         checkAndCallUnload(entityID);
-        checkAndCallPreload(entityID);
+        checkAndCallPreload(entityID, reload);
     }
 }
 
-void EntityTreeRenderer::checkAndCallPreload(const EntityItemID& entityID) {
+void EntityTreeRenderer::checkAndCallPreload(const EntityItemID& entityID, const bool reload) {
     if (_tree && !_shuttingDown) {
         // load the entity script if needed...
-        QScriptValue entityScript = loadEntityScript(entityID, true); // is preload!
+        QScriptValue entityScript = loadEntityScript(entityID, true, reload); // is preload!
         if (entityScript.property("preload").isValid()) {
             QScriptValueList entityArgs = createEntityArgs(entityID);
             entityScript.property("preload").call(entityScript, entityArgs);
diff --git a/libraries/entities-renderer/src/EntityTreeRenderer.h b/libraries/entities-renderer/src/EntityTreeRenderer.h
index 56a8208eb4..bd6044516f 100644
--- a/libraries/entities-renderer/src/EntityTreeRenderer.h
+++ b/libraries/entities-renderer/src/EntityTreeRenderer.h
@@ -110,7 +110,7 @@ signals:
 public slots:
     void addingEntity(const EntityItemID& entityID);
     void deletingEntity(const EntityItemID& entityID);
-    void entitySciptChanging(const EntityItemID& entityID);
+    void entitySciptChanging(const EntityItemID& entityID, const bool reload);
     void entityCollisionWithEntity(const EntityItemID& idA, const EntityItemID& idB, const Collision& collision);
 
     // optional slots that can be wired to menu items
@@ -127,7 +127,7 @@ private:
 
     void applyZonePropertiesToScene(std::shared_ptr<ZoneEntityItem> zone);
     void renderElementProxy(EntityTreeElement* entityTreeElement, RenderArgs* args);
-    void checkAndCallPreload(const EntityItemID& entityID);
+    void checkAndCallPreload(const EntityItemID& entityID, const bool reload = false);
     void checkAndCallUnload(const EntityItemID& entityID);
 
     QList<Model*> _releasedModels;
@@ -148,10 +148,10 @@ private:
     ScriptEngine* _entitiesScriptEngine;
     ScriptEngine* _sandboxScriptEngine;
 
-    QScriptValue loadEntityScript(EntityItemPointer entity, bool isPreload = false);
-    QScriptValue loadEntityScript(const EntityItemID& entityItemID, bool isPreload = false);
+    QScriptValue loadEntityScript(EntityItemPointer entity, bool isPreload = false, bool reload = false);
+    QScriptValue loadEntityScript(const EntityItemID& entityItemID, bool isPreload = false, bool reload = false);
     QScriptValue getPreviouslyLoadedEntityScript(const EntityItemID& entityItemID);
-    QString loadScriptContents(const QString& scriptMaybeURLorText, bool& isURL, bool& isPending, QUrl& url);
+    QString loadScriptContents(const QString& scriptMaybeURLorText, bool& isURL, bool& isPending, QUrl& url, bool& reload);
     QScriptValueList createMouseEventArgs(const EntityItemID& entityID, QMouseEvent* event, unsigned int deviceID);
     QScriptValueList createMouseEventArgs(const EntityItemID& entityID, const MouseEvent& mouseEvent);
     
diff --git a/libraries/entities/src/EntityItem.cpp b/libraries/entities/src/EntityItem.cpp
index da5f96f503..74b7a36504 100644
--- a/libraries/entities/src/EntityItem.cpp
+++ b/libraries/entities/src/EntityItem.cpp
@@ -54,6 +54,7 @@ EntityItem::EntityItem(const EntityItemID& entityItemID) :
     _friction(ENTITY_ITEM_DEFAULT_FRICTION),
     _lifetime(ENTITY_ITEM_DEFAULT_LIFETIME),
     _script(ENTITY_ITEM_DEFAULT_SCRIPT),
+    _scriptTimestamp(ENTITY_ITEM_DEFAULT_SCRIPT_TIMESTAMP),
     _collisionSoundURL(ENTITY_ITEM_DEFAULT_COLLISION_SOUND_URL),
     _registrationPoint(ENTITY_ITEM_DEFAULT_REGISTRATION_POINT),
     _angularVelocity(ENTITY_ITEM_DEFAULT_ANGULAR_VELOCITY),
@@ -107,6 +108,7 @@ EntityPropertyFlags EntityItem::getEntityProperties(EncodeBitstreamParams& param
     requestedProperties += PROP_FRICTION;
     requestedProperties += PROP_LIFETIME;
     requestedProperties += PROP_SCRIPT;
+    requestedProperties += PROP_SCRIPT_TIMESTAMP;
     requestedProperties += PROP_COLLISION_SOUND_URL;
     requestedProperties += PROP_REGISTRATION_POINT;
     requestedProperties += PROP_ANGULAR_VELOCITY;
@@ -238,6 +240,7 @@ OctreeElement::AppendState EntityItem::appendEntityData(OctreePacketData* packet
         APPEND_ENTITY_PROPERTY(PROP_FRICTION, getFriction());
         APPEND_ENTITY_PROPERTY(PROP_LIFETIME, getLifetime());
         APPEND_ENTITY_PROPERTY(PROP_SCRIPT, getScript());
+        APPEND_ENTITY_PROPERTY(PROP_SCRIPT_TIMESTAMP, getScriptTimestamp());
         APPEND_ENTITY_PROPERTY(PROP_REGISTRATION_POINT, getRegistrationPoint());
         APPEND_ENTITY_PROPERTY(PROP_ANGULAR_VELOCITY, getAngularVelocity());
         APPEND_ENTITY_PROPERTY(PROP_ANGULAR_DAMPING, getAngularDamping());
@@ -555,6 +558,7 @@ int EntityItem::readEntityDataFromBuffer(const unsigned char* data, int bytesLef
     READ_ENTITY_PROPERTY(PROP_FRICTION, float, updateFriction);
     READ_ENTITY_PROPERTY(PROP_LIFETIME, float, updateLifetime);
     READ_ENTITY_PROPERTY(PROP_SCRIPT, QString, setScript);
+    READ_ENTITY_PROPERTY(PROP_SCRIPT_TIMESTAMP, quint64, setScriptTimestamp);
     READ_ENTITY_PROPERTY(PROP_REGISTRATION_POINT, glm::vec3, setRegistrationPoint);
     READ_ENTITY_PROPERTY(PROP_ANGULAR_VELOCITY, glm::vec3, updateAngularVelocity);
     //READ_ENTITY_PROPERTY(PROP_ANGULAR_VELOCITY, glm::vec3, updateAngularVelocityInDegrees);
@@ -901,6 +905,7 @@ EntityItemProperties EntityItem::getProperties() const {
     COPY_ENTITY_PROPERTY_TO_PROPERTIES(created, getCreated);
     COPY_ENTITY_PROPERTY_TO_PROPERTIES(lifetime, getLifetime);
     COPY_ENTITY_PROPERTY_TO_PROPERTIES(script, getScript);
+    COPY_ENTITY_PROPERTY_TO_PROPERTIES(scriptTimestamp, getScriptTimestamp);
     COPY_ENTITY_PROPERTY_TO_PROPERTIES(collisionSoundURL, getCollisionSoundURL);
     COPY_ENTITY_PROPERTY_TO_PROPERTIES(registrationPoint, getRegistrationPoint);
     COPY_ENTITY_PROPERTY_TO_PROPERTIES(angularVelocity, getAngularVelocity);
@@ -967,6 +972,7 @@ bool EntityItem::setProperties(const EntityItemProperties& properties) {
 
     // non-simulation properties below
     SET_ENTITY_PROPERTY_FROM_PROPERTIES(script, setScript);
+    SET_ENTITY_PROPERTY_FROM_PROPERTIES(scriptTimestamp, setScriptTimestamp);
     SET_ENTITY_PROPERTY_FROM_PROPERTIES(collisionSoundURL, setCollisionSoundURL);
     SET_ENTITY_PROPERTY_FROM_PROPERTIES(glowLevel, setGlowLevel);
     SET_ENTITY_PROPERTY_FROM_PROPERTIES(localRenderAlpha, setLocalRenderAlpha);
diff --git a/libraries/entities/src/EntityItem.h b/libraries/entities/src/EntityItem.h
index b27129c124..3ce3a8e269 100644
--- a/libraries/entities/src/EntityItem.h
+++ b/libraries/entities/src/EntityItem.h
@@ -276,6 +276,10 @@ public:
 
     const QString& getScript() const { return _script; }
     void setScript(const QString& value) { _script = value; }
+
+    quint64 getScriptTimestamp() const { return _scriptTimestamp; }
+    void setScriptTimestamp(const quint64 value) { _scriptTimestamp = value; }
+
     const QString& getCollisionSoundURL() const { return _collisionSoundURL; }
     void setCollisionSoundURL(const QString& value) { _collisionSoundURL = value; }
 
@@ -412,6 +416,7 @@ protected:
     float _friction;
     float _lifetime;
     QString _script;
+    quint64 _scriptTimestamp;
     QString _collisionSoundURL;
     glm::vec3 _registrationPoint;
     glm::vec3 _angularVelocity;
diff --git a/libraries/entities/src/EntityItemProperties.cpp b/libraries/entities/src/EntityItemProperties.cpp
index cab96eb2e6..f755cd49fb 100644
--- a/libraries/entities/src/EntityItemProperties.cpp
+++ b/libraries/entities/src/EntityItemProperties.cpp
@@ -51,6 +51,7 @@ CONSTRUCT_PROPERTY(friction, ENTITY_ITEM_DEFAULT_FRICTION),
 CONSTRUCT_PROPERTY(lifetime, ENTITY_ITEM_DEFAULT_LIFETIME),
 CONSTRUCT_PROPERTY(created, UNKNOWN_CREATED_TIME),
 CONSTRUCT_PROPERTY(script, ENTITY_ITEM_DEFAULT_SCRIPT),
+CONSTRUCT_PROPERTY(scriptTimestamp, ENTITY_ITEM_DEFAULT_SCRIPT_TIMESTAMP),
 CONSTRUCT_PROPERTY(collisionSoundURL, ENTITY_ITEM_DEFAULT_COLLISION_SOUND_URL),
 CONSTRUCT_PROPERTY(color, ),
 CONSTRUCT_PROPERTY(modelURL, ""),
@@ -300,6 +301,7 @@ EntityPropertyFlags EntityItemProperties::getChangedProperties() const {
     CHECK_PROPERTY_CHANGE(PROP_FRICTION, friction);
     CHECK_PROPERTY_CHANGE(PROP_LIFETIME, lifetime);
     CHECK_PROPERTY_CHANGE(PROP_SCRIPT, script);
+    CHECK_PROPERTY_CHANGE(PROP_SCRIPT_TIMESTAMP, scriptTimestamp);
     CHECK_PROPERTY_CHANGE(PROP_COLLISION_SOUND_URL, collisionSoundURL);
     CHECK_PROPERTY_CHANGE(PROP_COLOR, color);
     CHECK_PROPERTY_CHANGE(PROP_MODEL_URL, modelURL);
@@ -393,6 +395,7 @@ QScriptValue EntityItemProperties::copyToScriptValue(QScriptEngine* engine, bool
     COPY_PROPERTY_TO_QSCRIPTVALUE_GETTER(created, created.toString(Qt::ISODate));
 
     COPY_PROPERTY_TO_QSCRIPTVALUE(script);
+    COPY_PROPERTY_TO_QSCRIPTVALUE(scriptTimestamp);
     COPY_PROPERTY_TO_QSCRIPTVALUE(registrationPoint);
     COPY_PROPERTY_TO_QSCRIPTVALUE(angularVelocity);
     COPY_PROPERTY_TO_QSCRIPTVALUE(angularDamping);
@@ -506,6 +509,7 @@ void EntityItemProperties::copyFromScriptValue(const QScriptValue& object, bool
     COPY_PROPERTY_FROM_QSCRIPTVALUE(friction, float, setFriction);
     COPY_PROPERTY_FROM_QSCRIPTVALUE(lifetime, float, setLifetime);
     COPY_PROPERTY_FROM_QSCRIPTVALUE(script, QString, setScript);
+    COPY_PROPERTY_FROM_QSCRIPTVALUE(scriptTimestamp, quint64, setScriptTimestamp);
     COPY_PROPERTY_FROM_QSCRIPTVALUE(registrationPoint, glmVec3, setRegistrationPoint);
     COPY_PROPERTY_FROM_QSCRIPTVALUE(angularVelocity, glmVec3, setAngularVelocity);
     COPY_PROPERTY_FROM_QSCRIPTVALUE(angularDamping, float, setAngularDamping);
@@ -713,6 +717,7 @@ bool EntityItemProperties::encodeEntityEditPacket(PacketType command, EntityItem
             APPEND_ENTITY_PROPERTY(PROP_FRICTION, properties.getFriction());
             APPEND_ENTITY_PROPERTY(PROP_LIFETIME, properties.getLifetime());
             APPEND_ENTITY_PROPERTY(PROP_SCRIPT, properties.getScript());
+            APPEND_ENTITY_PROPERTY(PROP_SCRIPT_TIMESTAMP, properties.getScriptTimestamp());
             APPEND_ENTITY_PROPERTY(PROP_COLOR, properties.getColor());
             APPEND_ENTITY_PROPERTY(PROP_REGISTRATION_POINT, properties.getRegistrationPoint());
             APPEND_ENTITY_PROPERTY(PROP_ANGULAR_VELOCITY, properties.getAngularVelocity());
@@ -966,7 +971,8 @@ bool EntityItemProperties::decodeEntityEditPacket(const unsigned char* data, int
     READ_ENTITY_PROPERTY_TO_PROPERTIES(PROP_RESTITUTION, float, setRestitution);
     READ_ENTITY_PROPERTY_TO_PROPERTIES(PROP_FRICTION, float, setFriction);
     READ_ENTITY_PROPERTY_TO_PROPERTIES(PROP_LIFETIME, float, setLifetime);
-    READ_ENTITY_PROPERTY_TO_PROPERTIES(PROP_SCRIPT,QString, setScript);
+    READ_ENTITY_PROPERTY_TO_PROPERTIES(PROP_SCRIPT, QString, setScript);
+    READ_ENTITY_PROPERTY_TO_PROPERTIES(PROP_SCRIPT_TIMESTAMP, quint64, setScriptTimestamp);
     READ_ENTITY_PROPERTY_TO_PROPERTIES(PROP_COLOR, xColor, setColor);
     READ_ENTITY_PROPERTY_TO_PROPERTIES(PROP_REGISTRATION_POINT, glm::vec3, setRegistrationPoint);
     READ_ENTITY_PROPERTY_TO_PROPERTIES(PROP_ANGULAR_VELOCITY, glm::vec3, setAngularVelocity);
@@ -1106,6 +1112,7 @@ void EntityItemProperties::markAllChanged() {
     _userDataChanged = true;
     _simulatorIDChanged = true;
     _scriptChanged = true;
+    _scriptTimestampChanged = true;
     _collisionSoundURLChanged = true;
     _registrationPointChanged = true;
     _angularVelocityChanged = true;
diff --git a/libraries/entities/src/EntityItemProperties.h b/libraries/entities/src/EntityItemProperties.h
index 4772d08c44..fdf01c4761 100644
--- a/libraries/entities/src/EntityItemProperties.h
+++ b/libraries/entities/src/EntityItemProperties.h
@@ -98,6 +98,7 @@ public:
     DEFINE_PROPERTY(PROP_LIFETIME, Lifetime, lifetime, float);
     DEFINE_PROPERTY(PROP_CREATED, Created, created, quint64);
     DEFINE_PROPERTY_REF(PROP_SCRIPT, Script, script, QString);
+    DEFINE_PROPERTY(PROP_SCRIPT_TIMESTAMP, ScriptTimestamp, scriptTimestamp, quint64);
     DEFINE_PROPERTY_REF(PROP_COLLISION_SOUND_URL, CollisionSoundURL, collisionSoundURL, QString);
     DEFINE_PROPERTY_REF(PROP_COLOR, Color, color, xColor);
     DEFINE_PROPERTY_REF(PROP_MODEL_URL, ModelURL, modelURL, QString);
@@ -262,6 +263,7 @@ inline QDebug operator<<(QDebug debug, const EntityItemProperties& properties) {
     DEBUG_PROPERTY_IF_CHANGED(debug, properties, Friction, friction, "");
     DEBUG_PROPERTY_IF_CHANGED(debug, properties, Lifetime, lifetime, "");
     DEBUG_PROPERTY_IF_CHANGED(debug, properties, Script, script, "");
+    DEBUG_PROPERTY_IF_CHANGED(debug, properties, ScriptTimestamp, scriptTimestamp, "");
     DEBUG_PROPERTY_IF_CHANGED(debug, properties, CollisionSoundURL, collisionSoundURL, "");
     DEBUG_PROPERTY_IF_CHANGED(debug, properties, Color, color, "");
     DEBUG_PROPERTY_IF_CHANGED(debug, properties, ModelURL, modelURL, "");
diff --git a/libraries/entities/src/EntityItemPropertiesDefaults.h b/libraries/entities/src/EntityItemPropertiesDefaults.h
index 1e3a016049..0cdfe73040 100644
--- a/libraries/entities/src/EntityItemPropertiesDefaults.h
+++ b/libraries/entities/src/EntityItemPropertiesDefaults.h
@@ -32,6 +32,7 @@ const float ENTITY_ITEM_DEFAULT_GLOW_LEVEL = 0.0f;
 const bool ENTITY_ITEM_DEFAULT_VISIBLE = true;
 
 const QString ENTITY_ITEM_DEFAULT_SCRIPT = QString("");
+const quint64 ENTITY_ITEM_DEFAULT_SCRIPT_TIMESTAMP = 0;
 const QString ENTITY_ITEM_DEFAULT_COLLISION_SOUND_URL = QString("");
 const glm::vec3 ENTITY_ITEM_DEFAULT_REGISTRATION_POINT = ENTITY_ITEM_HALF_VEC3; // center
 
diff --git a/libraries/entities/src/EntityItemPropertiesMacros.h b/libraries/entities/src/EntityItemPropertiesMacros.h
index 0f3459e5d2..d4fcfa8cab 100644
--- a/libraries/entities/src/EntityItemPropertiesMacros.h
+++ b/libraries/entities/src/EntityItemPropertiesMacros.h
@@ -92,6 +92,7 @@ inline QScriptValue convertScriptValue(QScriptEngine* e, const glm::vec3& v) { r
 inline QScriptValue convertScriptValue(QScriptEngine* e, float v) { return QScriptValue(v); }
 inline QScriptValue convertScriptValue(QScriptEngine* e, int v) { return QScriptValue(v); }
 inline QScriptValue convertScriptValue(QScriptEngine* e, quint32 v) { return QScriptValue(v); }
+inline QScriptValue convertScriptValue(QScriptEngine* e, quint64 v) { return QScriptValue((qsreal)v); }
 inline QScriptValue convertScriptValue(QScriptEngine* e, const QString& v) { return QScriptValue(v); }
 
 inline QScriptValue convertScriptValue(QScriptEngine* e, const xColor& v) { return xColorToScriptValue(e, v); }
@@ -134,6 +135,7 @@ typedef glm::vec3 glmVec3;
 typedef glm::quat glmQuat;
 typedef QVector<glm::vec3> qVectorVec3;
 inline float float_convertFromScriptValue(const QScriptValue& v, bool& isValid) { return v.toVariant().toFloat(&isValid); }
+inline quint64 quint64_convertFromScriptValue(const QScriptValue& v, bool& isValid) { return v.toVariant().toULongLong(&isValid); }
 inline uint16_t uint16_t_convertFromScriptValue(const QScriptValue& v, bool& isValid) { return v.toVariant().toInt(&isValid); }
 inline int int_convertFromScriptValue(const QScriptValue& v, bool& isValid) { return v.toVariant().toInt(&isValid); }
 inline bool bool_convertFromScriptValue(const QScriptValue& v, bool& isValid) { isValid = true; return v.toVariant().toBool(); }
diff --git a/libraries/entities/src/EntityPropertyFlags.h b/libraries/entities/src/EntityPropertyFlags.h
index 5e35419ba2..e83a69227f 100644
--- a/libraries/entities/src/EntityPropertyFlags.h
+++ b/libraries/entities/src/EntityPropertyFlags.h
@@ -123,6 +123,7 @@ enum EntityPropertyList {
     PROP_DESCRIPTION,
     
     PROP_FACE_CAMERA,
+    PROP_SCRIPT_TIMESTAMP,
     
     ////////////////////////////////////////////////////////////////////////////////////////////////////
     // ATTENTION: add new properties ABOVE this line
diff --git a/libraries/entities/src/EntityTree.cpp b/libraries/entities/src/EntityTree.cpp
index 363f3c56d7..752082932b 100644
--- a/libraries/entities/src/EntityTree.cpp
+++ b/libraries/entities/src/EntityTree.cpp
@@ -185,6 +185,7 @@ bool EntityTree::updateEntityWithElement(EntityItemPointer entity, const EntityI
         // else client accepts what the server says
 
         QString entityScriptBefore = entity->getScript();
+        quint64 entityScriptTimestampBefore = entity->getScriptTimestamp();
         QString collisionSoundURLBefore = entity->getCollisionSoundURL();
         uint32_t preFlags = entity->getDirtyFlags();
         UpdateEntityOperator theOperator(this, containingElement, entity, properties);
@@ -206,8 +207,10 @@ bool EntityTree::updateEntityWithElement(EntityItemPointer entity, const EntityI
         }
         
         QString entityScriptAfter = entity->getScript();
-        if (entityScriptBefore != entityScriptAfter) {
-            emitEntityScriptChanging(entity->getEntityItemID()); // the entity script has changed
+        quint64 entityScriptTimestampAfter = entity->getScriptTimestamp();
+        bool reload = entityScriptTimestampBefore != entityScriptTimestampAfter;
+        if (entityScriptBefore != entityScriptAfter || reload) {
+            emitEntityScriptChanging(entity->getEntityItemID(), reload); // the entity script has changed
         }
         maybeNotifyNewCollisionSoundURL(collisionSoundURLBefore, entity->getCollisionSoundURL());
      }
@@ -266,9 +269,10 @@ EntityItemPointer EntityTree::addEntity(const EntityItemID& entityID, const Enti
     return result;
 }
 
-void EntityTree::emitEntityScriptChanging(const EntityItemID& entityItemID) {
-    emit entityScriptChanging(entityItemID);
+void EntityTree::emitEntityScriptChanging(const EntityItemID& entityItemID, const bool reload) {
+    emit entityScriptChanging(entityItemID, reload);
 }
+
 void EntityTree::maybeNotifyNewCollisionSoundURL(const QString& previousCollisionSoundURL, const QString& nextCollisionSoundURL) {
     if (!nextCollisionSoundURL.isEmpty() && (nextCollisionSoundURL != previousCollisionSoundURL)) {
         emit newCollisionSoundURL(QUrl(nextCollisionSoundURL));
diff --git a/libraries/entities/src/EntityTree.h b/libraries/entities/src/EntityTree.h
index 1ad3ef6b1c..9c4be9a86f 100644
--- a/libraries/entities/src/EntityTree.h
+++ b/libraries/entities/src/EntityTree.h
@@ -155,7 +155,7 @@ public:
 
     void entityChanged(EntityItemPointer entity);
 
-    void emitEntityScriptChanging(const EntityItemID& entityItemID);
+    void emitEntityScriptChanging(const EntityItemID& entityItemID, const bool reload);
 
     void setSimulation(EntitySimulation* simulation);
     EntitySimulation* getSimulation() const { return _simulation; }
@@ -171,7 +171,7 @@ public:
 signals:
     void deletingEntity(const EntityItemID& entityID);
     void addingEntity(const EntityItemID& entityID);
-    void entityScriptChanging(const EntityItemID& entityItemID);
+    void entityScriptChanging(const EntityItemID& entityItemID, const bool reload);
     void newCollisionSoundURL(const QUrl& url);
     void clearingEntities();
 
diff --git a/libraries/entities/src/EntityTreeElement.cpp b/libraries/entities/src/EntityTreeElement.cpp
index 80333a44e5..4bc81e1da6 100644
--- a/libraries/entities/src/EntityTreeElement.cpp
+++ b/libraries/entities/src/EntityTreeElement.cpp
@@ -733,6 +733,7 @@ int EntityTreeElement::readElementDataFromBuffer(const unsigned char* data, int
                 //    3) remember the old cube for the entity so we can mark it as dirty
                 if (entityItem) {
                     QString entityScriptBefore = entityItem->getScript();
+                    quint64 entityScriptTimestampBefore = entityItem->getScriptTimestamp();
                     bool bestFitBefore = bestFitEntityBounds(entityItem);
                     EntityTreeElement* currentContainingElement = _myTree->getContainingElement(entityItemID);
 
@@ -755,8 +756,10 @@ int EntityTreeElement::readElementDataFromBuffer(const unsigned char* data, int
                     }
 
                     QString entityScriptAfter = entityItem->getScript();
-                    if (entityScriptBefore != entityScriptAfter) {
-                        _myTree->emitEntityScriptChanging(entityItemID); // the entity script has changed
+                    quint64 entityScriptTimestampAfter = entityItem->getScriptTimestamp();
+                    bool reload = entityScriptTimestampBefore != entityScriptTimestampAfter;
+                    if (entityScriptBefore != entityScriptAfter || reload) {
+                        _myTree->emitEntityScriptChanging(entityItemID, reload); // the entity script has changed
                     }
 
                 } else {
diff --git a/libraries/networking/src/PacketHeaders.cpp b/libraries/networking/src/PacketHeaders.cpp
index 29a670761a..5fe9bbbb99 100644
--- a/libraries/networking/src/PacketHeaders.cpp
+++ b/libraries/networking/src/PacketHeaders.cpp
@@ -73,7 +73,7 @@ PacketVersion versionForPacketType(PacketType packetType) {
         case PacketTypeEntityAdd:
         case PacketTypeEntityEdit:
         case PacketTypeEntityData:
-            return VERSION_ENTITIES_FACE_CAMERA;
+            return VERSION_ENTITIES_SCRIPT_TIMESTAMP_FIX;
         case PacketTypeEntityErase:
             return 2;
         case PacketTypeAudioStreamStats:
diff --git a/libraries/networking/src/PacketHeaders.h b/libraries/networking/src/PacketHeaders.h
index 1d064c3399..789675ec00 100644
--- a/libraries/networking/src/PacketHeaders.h
+++ b/libraries/networking/src/PacketHeaders.h
@@ -184,5 +184,7 @@ const PacketVersion VERSION_NO_ENTITY_ID_SWAP = 27;
 const PacketVersion VERSION_ENTITIES_PARTICLE_FIX = 28;
 const PacketVersion VERSION_ENTITIES_LINE_POINTS = 29;
 const PacketVersion VERSION_ENTITIES_FACE_CAMERA = 30;
+const PacketVersion VERSION_ENTITIES_SCRIPT_TIMESTAMP = 31;
+const PacketVersion VERSION_ENTITIES_SCRIPT_TIMESTAMP_FIX = 32;
 
 #endif // hifi_PacketHeaders_h
diff --git a/libraries/script-engine/src/ScriptCache.cpp b/libraries/script-engine/src/ScriptCache.cpp
index 8f854cfdc3..2047442ce6 100644
--- a/libraries/script-engine/src/ScriptCache.cpp
+++ b/libraries/script-engine/src/ScriptCache.cpp
@@ -16,18 +16,22 @@
 #include <QNetworkReply>
 #include <QObject>
 
+#include <assert.h>
 #include <NetworkAccessManager.h>
 #include <SharedUtil.h>
-#include "ScriptEngineLogging.h"
+
 #include "ScriptCache.h"
+#include "ScriptEngineLogging.h"
 
 ScriptCache::ScriptCache(QObject* parent) {
     // nothing to do here...
 }
 
-QString ScriptCache::getScript(const QUrl& url, ScriptUser* scriptUser, bool& isPending) {
+QString ScriptCache::getScript(const QUrl& url, ScriptUser* scriptUser, bool& isPending, bool reload) {
+    assert(!_scriptCache.contains(url) || !reload);
+
     QString scriptContents;
-    if (_scriptCache.contains(url)) {
+    if (_scriptCache.contains(url) && !reload) {
         qCDebug(scriptengine) << "Found script in cache:" << url.toString();
         scriptContents = _scriptCache[url];
         scriptUser->scriptContentsAvailable(url, scriptContents);
@@ -43,8 +47,13 @@ QString ScriptCache::getScript(const QUrl& url, ScriptUser* scriptUser, bool& is
             QNetworkAccessManager& networkAccessManager = NetworkAccessManager::getInstance();
             QNetworkRequest networkRequest = QNetworkRequest(url);
             networkRequest.setHeader(QNetworkRequest::UserAgentHeader, HIGH_FIDELITY_USER_AGENT);
+            if (reload) {
+                networkRequest.setAttribute(QNetworkRequest::CacheLoadControlAttribute, QNetworkRequest::AlwaysNetwork);
+                qCDebug(scriptengine) << "Redownloading script at:" << url.toString();
+            } else {
+                qCDebug(scriptengine) << "Downloading script at:" << url.toString();
+            }
 
-            qCDebug(scriptengine) << "Downloading script at" << url.toString();
             QNetworkReply* reply = networkAccessManager.get(networkRequest);
             connect(reply, &QNetworkReply::finished, this, &ScriptCache::scriptDownloaded);
         }
@@ -52,6 +61,13 @@ QString ScriptCache::getScript(const QUrl& url, ScriptUser* scriptUser, bool& is
     return scriptContents;
 }
 
+void ScriptCache::deleteScript(const QUrl& url) {
+    if (_scriptCache.contains(url)) {
+        qCDebug(scriptengine) << "Delete script from cache:" << url.toString();
+        _scriptCache.remove(url);
+    }
+}
+
 void ScriptCache::scriptDownloaded() {
     QNetworkReply* reply = qobject_cast<QNetworkReply*>(sender());
     QUrl url = reply->url();
diff --git a/libraries/script-engine/src/ScriptCache.h b/libraries/script-engine/src/ScriptCache.h
index 16bf04c53e..25a36c04d8 100644
--- a/libraries/script-engine/src/ScriptCache.h
+++ b/libraries/script-engine/src/ScriptCache.h
@@ -26,7 +26,8 @@ class ScriptCache : public QObject, public Dependency {
     SINGLETON_DEPENDENCY
 
 public:
-    QString getScript(const QUrl& url, ScriptUser* scriptUser, bool& isPending);
+    QString getScript(const QUrl& url, ScriptUser* scriptUser, bool& isPending, bool redownload = false);
+    void deleteScript(const QUrl& url);
     void addScriptToBadScriptList(const QUrl& url) { _badScripts.insert(url); }
     bool isInBadScriptList(const QUrl& url) { return _badScripts.contains(url); }
     
diff --git a/libraries/script-engine/src/ScriptEngine.cpp b/libraries/script-engine/src/ScriptEngine.cpp
index 0945a556f2..55cf9e9890 100644
--- a/libraries/script-engine/src/ScriptEngine.cpp
+++ b/libraries/script-engine/src/ScriptEngine.cpp
@@ -94,6 +94,7 @@ ScriptEngine::ScriptEngine(const QString& scriptContents, const QString& fileNam
     _vec3Library(),
     _uuidLibrary(),
     _isUserLoaded(false),
+    _isReloading(false),
     _arrayBufferClass(new ArrayBufferClass(this))
 {
     _allScriptsMutex.lock();
@@ -251,12 +252,13 @@ bool ScriptEngine::setScriptContents(const QString& scriptContents, const QStrin
     return true;
 }
 
-void ScriptEngine::loadURL(const QUrl& scriptURL) {
+void ScriptEngine::loadURL(const QUrl& scriptURL, bool reload) {
     if (_isRunning) {
         return;
     }
 
     _fileNameString = scriptURL.toString();
+    _isReloading = reload;
     
     QUrl url(scriptURL);
     
@@ -283,8 +285,7 @@ void ScriptEngine::loadURL(const QUrl& scriptURL) {
         } else {
             bool isPending;
             auto scriptCache = DependencyManager::get<ScriptCache>();
-            scriptCache->getScript(url, this, isPending);
-            
+            scriptCache->getScript(url, this, isPending, reload);
         }
     }
 }
@@ -904,7 +905,13 @@ void ScriptEngine::load(const QString& loadFile) {
     }
 
     QUrl url = resolvePath(loadFile);
-    emit loadScript(url.toString(), false);
+    if (_isReloading) {
+        auto scriptCache = DependencyManager::get<ScriptCache>();
+        scriptCache->deleteScript(url.toString());
+        emit reloadScript(url.toString(), false);
+    } else {
+        emit loadScript(url.toString(), false);
+    }
 }
 
 void ScriptEngine::nodeKilled(SharedNodePointer node) {
diff --git a/libraries/script-engine/src/ScriptEngine.h b/libraries/script-engine/src/ScriptEngine.h
index ec28804049..a96042184d 100644
--- a/libraries/script-engine/src/ScriptEngine.h
+++ b/libraries/script-engine/src/ScriptEngine.h
@@ -104,7 +104,7 @@ public:
     Q_INVOKABLE void removeEventHandler(const EntityItemID& entityID, const QString& eventName, QScriptValue handler);
 
 public slots:
-    void loadURL(const QUrl& scriptURL);
+    void loadURL(const QUrl& scriptURL, bool reload);
     void stop();
 
     QScriptValue evaluate(const QString& program, const QString& fileName = QString(), int lineNumber = 1);
@@ -132,6 +132,7 @@ signals:
     void runningStateChanged();
     void evaluationFinished(QScriptValue result, bool isException);
     void loadScript(const QString& scriptName, bool isUserLoaded);
+    void reloadScript(const QString& scriptName, bool isUserLoaded);
     void doneRunning();
 
 protected:
@@ -165,6 +166,7 @@ private:
     Vec3 _vec3Library;
     ScriptUUID _uuidLibrary;
     bool _isUserLoaded;
+    bool _isReloading;
 
     ArrayBufferClass* _arrayBufferClass;