diff --git a/examples/edit.js b/examples/edit.js
index 2974397cde..e61822558c 100644
--- a/examples/edit.js
+++ b/examples/edit.js
@@ -1349,6 +1349,15 @@ 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 27a2929d1c..b4b336fbda 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",
@@ -1138,7 +1148,10 @@
         </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 dd2e96ab43..8564479ac7 100644
--- a/examples/html/style.css
+++ b/examples/html/style.css
@@ -250,6 +250,11 @@ 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/libraries/entities-renderer/src/EntityTreeRenderer.cpp b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
index e1bd01547e..845c870d90 100644
--- a/libraries/entities-renderer/src/EntityTreeRenderer.cpp
+++ b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
@@ -155,13 +155,14 @@ 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);
     
@@ -199,7 +200,7 @@ 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);
             }
         }
     }
@@ -208,7 +209,7 @@ 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
     }
@@ -228,8 +229,8 @@ 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
         }
         
@@ -244,7 +245,7 @@ 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);
@@ -1029,17 +1030,17 @@ 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 e491524c78..451aed6ce5 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 d2881e5f3a..63a770ab7a 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 73f9127361..8d9ad244ef 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; }
+
+    const 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 cbb3b1dc31..471d191d17 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, ""),
@@ -299,6 +300,7 @@ 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);
@@ -391,6 +393,7 @@ 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);
@@ -503,6 +506,7 @@ 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);
@@ -710,6 +714,7 @@ 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());
@@ -961,7 +966,8 @@ 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);
@@ -1099,6 +1105,7 @@ 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 068bc98f7e..294aab7f75 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);
@@ -259,6 +260,7 @@ 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 11341b160c..7ca93a3f33 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 f1ebdb8a1f..666f9e0346 100644
--- a/libraries/entities/src/EntityPropertyFlags.h
+++ b/libraries/entities/src/EntityPropertyFlags.h
@@ -55,6 +55,7 @@ enum EntityPropertyList {
     PROP_DAMPING,
     PROP_LIFETIME,
     PROP_SCRIPT,
+    PROP_SCRIPT_TIMESTAMP,
 
     // these properties are supported by some derived classes
     PROP_COLOR,
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 78bb3f11e1..f989c417f0 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_LINE_POINTS;
+            return VERSION_ENTITIES_SCRIPT_TIMESTAMP;
         case PacketTypeEntityErase:
             return 2;
         case PacketTypeAudioStreamStats:
diff --git a/libraries/networking/src/PacketHeaders.h b/libraries/networking/src/PacketHeaders.h
index 228df1cdde..5780e7bec2 100644
--- a/libraries/networking/src/PacketHeaders.h
+++ b/libraries/networking/src/PacketHeaders.h
@@ -183,5 +183,6 @@ const PacketVersion VERSION_ENTITIES_HAVE_FRICTION = 26;
 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_SCRIPT_TIMESTAMP = 30;
 
 #endif // hifi_PacketHeaders_h
diff --git a/libraries/script-engine/src/ScriptCache.cpp b/libraries/script-engine/src/ScriptCache.cpp
index ae16494af3..2047442ce6 100644
--- a/libraries/script-engine/src/ScriptCache.cpp
+++ b/libraries/script-engine/src/ScriptCache.cpp
@@ -27,11 +27,11 @@ ScriptCache::ScriptCache(QObject* parent) {
     // nothing to do here...
 }
 
-QString ScriptCache::getScript(const QUrl& url, ScriptUser* scriptUser, bool& isPending, bool redownload) {
-    assert(!_scriptCache.contains(url) || !redownload);
+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);
@@ -47,8 +47,8 @@ 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 (redownload) {
-                networkRequest.setAttribute(QNetworkRequest::CacheLoadControlAttribute, QNetworkRequest::PreferNetwork);
+            if (reload) {
+                networkRequest.setAttribute(QNetworkRequest::CacheLoadControlAttribute, QNetworkRequest::AlwaysNetwork);
                 qCDebug(scriptengine) << "Redownloading script at:" << url.toString();
             } else {
                 qCDebug(scriptengine) << "Downloading script at:" << url.toString();