diff --git a/assignment-client/src/Agent.cpp b/assignment-client/src/Agent.cpp
index 9d50f60c01..5e5bbba0bf 100644
--- a/assignment-client/src/Agent.cpp
+++ b/assignment-client/src/Agent.cpp
@@ -184,6 +184,7 @@ void Agent::run() {
     loop.exec();
     
     QString scriptContents(reply->readAll());
+    delete reply;
     
     qDebug() << "Downloaded script:" << scriptContents;
     
diff --git a/assignment-client/src/audio/AudioMixer.cpp b/assignment-client/src/audio/AudioMixer.cpp
index 0311f8562b..6b646c1dad 100644
--- a/assignment-client/src/audio/AudioMixer.cpp
+++ b/assignment-client/src/audio/AudioMixer.cpp
@@ -60,7 +60,7 @@
 #include "AudioMixer.h"
 
 const float LOUDNESS_TO_DISTANCE_RATIO = 0.00001f;
-const float DEFAULT_ATTENUATION_PER_DOUBLING_IN_DISTANCE = 0.18;
+const float DEFAULT_ATTENUATION_PER_DOUBLING_IN_DISTANCE = 0.18f;
 const float DEFAULT_NOISE_MUTING_THRESHOLD = 0.003f;
 const QString AUDIO_MIXER_LOGGING_TARGET_NAME = "audio-mixer";
 const QString AUDIO_ENV_GROUP_KEY = "audio_env";
diff --git a/domain-server/src/DomainServer.cpp b/domain-server/src/DomainServer.cpp
index 3da06a9c0e..a094432af2 100644
--- a/domain-server/src/DomainServer.cpp
+++ b/domain-server/src/DomainServer.cpp
@@ -1736,6 +1736,9 @@ bool DomainServer::handleHTTPSRequest(HTTPSConnection* connection, const QUrl &u
                 connection->respond(HTTPConnection::StatusCode302, QByteArray(),
                                     HTTPConnection::DefaultContentType, cookieHeaders);
                 
+                delete tokenReply;
+                delete profileReply;
+                
                 // we've redirected the user back to our homepage
                 return true;
                 
diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index 1364e1b05b..22a2b6bc22 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -3770,9 +3770,9 @@ void Application::parseVersionXml() {
     QString latestVersion;
     QUrl downloadUrl;
     QString releaseNotes("Unavailable");
-    QObject* sender = QObject::sender();
+    QNetworkReply* sender = qobject_cast<QNetworkReply*>(QObject::sender());
 
-    QXmlStreamReader xml(qobject_cast<QNetworkReply*>(sender));
+    QXmlStreamReader xml(sender);
 
     while (!xml.atEnd() && !xml.hasError()) {
         if (xml.tokenType() == QXmlStreamReader::StartElement && xml.name() == operatingSystem) {
diff --git a/interface/src/avatar/Avatar.cpp b/interface/src/avatar/Avatar.cpp
index ddbaeece72..5b10cbd1a5 100644
--- a/interface/src/avatar/Avatar.cpp
+++ b/interface/src/avatar/Avatar.cpp
@@ -454,47 +454,6 @@ void Avatar::render(const glm::vec3& cameraPosition, RenderMode renderMode, bool
         return;
     }
     renderDisplayName();
-    
-    if (!_chatMessage.empty()) {
-        int width = 0;
-        int lastWidth = 0;
-        for (string::iterator it = _chatMessage.begin(); it != _chatMessage.end(); it++) {
-            width += (lastWidth = textRenderer(CHAT)->computeWidth(*it));
-        }
-        glPushMatrix();
-        
-        glm::vec3 chatPosition = getHead()->getEyePosition() + getBodyUpDirection() * CHAT_MESSAGE_HEIGHT * _scale;
-        glTranslatef(chatPosition.x, chatPosition.y, chatPosition.z);
-        glm::quat chatRotation = Application::getInstance()->getCamera()->getRotation();
-        glm::vec3 chatAxis = glm::axis(chatRotation);
-        glRotatef(glm::degrees(glm::angle(chatRotation)), chatAxis.x, chatAxis.y, chatAxis.z);
-        
-        glColor3f(0.0f, 0.8f, 0.0f);
-        glRotatef(180.0f, 0.0f, 1.0f, 0.0f);
-        glRotatef(180.0f, 0.0f, 0.0f, 1.0f);
-        glScalef(_scale * CHAT_MESSAGE_SCALE, _scale * CHAT_MESSAGE_SCALE, 1.0f);
-        
-        glDisable(GL_LIGHTING);
-        glDepthMask(false);
-        if (_keyState == NO_KEY_DOWN) {
-            textRenderer(CHAT)->draw(-width / 2.0f, 0, _chatMessage.c_str());
-            
-        } else {
-            // rather than using substr and allocating a new string, just replace the last
-            // character with a null, then restore it
-            int lastIndex = _chatMessage.size() - 1;
-            char lastChar = _chatMessage[lastIndex];
-            _chatMessage[lastIndex] = '\0';
-            textRenderer(CHAT)->draw(-width / 2.0f, 0, _chatMessage.c_str());
-            _chatMessage[lastIndex] = lastChar;
-            glColor3f(0.0f, 1.0f, 0.0f);
-            textRenderer(CHAT)->draw(width / 2.0f - lastWidth, 0, _chatMessage.c_str() + lastIndex);
-        }
-        glEnable(GL_LIGHTING);
-        glDepthMask(true);
-        
-        glPopMatrix();
-    }
 }
 
 glm::quat Avatar::computeRotationFromBodyToWorldUp(float proportion) const {
diff --git a/interface/src/avatar/FaceModel.cpp b/interface/src/avatar/FaceModel.cpp
index 2e6c166bd3..3523cb2176 100644
--- a/interface/src/avatar/FaceModel.cpp
+++ b/interface/src/avatar/FaceModel.cpp
@@ -49,16 +49,22 @@ void FaceModel::maybeUpdateNeckRotation(const JointState& parentState, const FBX
     Avatar* owningAvatar = static_cast<Avatar*>(_owningHead->_owningAvatar);
     // get the rotation axes in joint space and use them to adjust the rotation
     glm::mat3 axes = glm::mat3_cast(glm::quat());
-    glm::mat3 inverse = glm::mat3(glm::inverse(parentState.getTransform() * glm::translate(state.getDefaultTranslationInConstrainedFrame()) *
-        joint.preTransform * glm::mat4_cast(joint.preRotation)));
-    state.setRotationInConstrainedFrame(
-        glm::angleAxis(- RADIANS_PER_DEGREE * (_owningHead->getFinalRoll() - owningAvatar->getHead()->getFinalLeanSideways()),
-                                                       glm::normalize(inverse * axes[2]))
-        * glm::angleAxis(RADIANS_PER_DEGREE * (_owningHead->getFinalYaw() - _owningHead->getTorsoTwist()),
-                         glm::normalize(inverse * axes[1]))
-        * glm::angleAxis(- RADIANS_PER_DEGREE * (_owningHead->getFinalPitch() - owningAvatar->getHead()->getFinalLeanForward()),
-                         glm::normalize(inverse * axes[0]))
-        * joint.rotation, DEFAULT_PRIORITY);
+    glm::mat3 inverse = glm::mat3(glm::inverse(parentState.getTransform() *
+                                               glm::translate(state.getDefaultTranslationInConstrainedFrame()) *
+                                               joint.preTransform * glm::mat4_cast(joint.preRotation)));
+    glm::vec3 pitchYawRoll = safeEulerAngles(_owningHead->getFinalOrientationInLocalFrame());
+    if (owningAvatar->isMyAvatar()) {
+        glm::vec3 lean = glm::radians(glm::vec3(_owningHead->getFinalLeanForward(),
+                                                _owningHead->getTorsoTwist(),
+                                                _owningHead->getFinalLeanSideways()));
+        pitchYawRoll -= lean;
+    }
+    
+    state.setRotationInConstrainedFrame(glm::angleAxis(-pitchYawRoll.z, glm::normalize(inverse * axes[2]))
+                                        * glm::angleAxis(pitchYawRoll.y, glm::normalize(inverse * axes[1]))
+                                        * glm::angleAxis(-pitchYawRoll.x, glm::normalize(inverse * axes[0]))
+                                        * joint.rotation, DEFAULT_PRIORITY);
+    
 }
 
 void FaceModel::maybeUpdateEyeRotation(Model* model, const JointState& parentState, const FBXJoint& joint, JointState& state) {
diff --git a/interface/src/ui/ScriptEditorWidget.cpp b/interface/src/ui/ScriptEditorWidget.cpp
index f4a509baa6..660b9009b6 100644
--- a/interface/src/ui/ScriptEditorWidget.cpp
+++ b/interface/src/ui/ScriptEditorWidget.cpp
@@ -158,6 +158,8 @@ void ScriptEditorWidget::loadFile(const QString& scriptPath) {
         QObject::connect(reply, &QNetworkReply::finished, &loop, &QEventLoop::quit);
         loop.exec();
         _scriptEditorWidgetUI->scriptEdit->setPlainText(reply->readAll());
+        delete reply;
+        
         if (!saveAs()) {
             static_cast<ScriptEditorWindow*>(this->parent()->parent()->parent())->terminateCurrentTab();
         }
diff --git a/interface/src/ui/SnapshotShareDialog.cpp b/interface/src/ui/SnapshotShareDialog.cpp
index 046aa4d12c..47914e0a12 100644
--- a/interface/src/ui/SnapshotShareDialog.cpp
+++ b/interface/src/ui/SnapshotShareDialog.cpp
@@ -148,6 +148,7 @@ void SnapshotShareDialog::postRequestFinished() {
 
     QNetworkReply* requestReply = reinterpret_cast<QNetworkReply*>(sender());
     QJsonDocument jsonResponse = QJsonDocument::fromJson(requestReply->readAll());
+    requestReply->deleteLater();
     const QJsonObject& responseObject = jsonResponse.object();
 
     if (responseObject.contains("id")) {
diff --git a/interface/src/ui/overlays/BillboardOverlay.cpp b/interface/src/ui/overlays/BillboardOverlay.cpp
index bcb69bdce3..b34416f566 100644
--- a/interface/src/ui/overlays/BillboardOverlay.cpp
+++ b/interface/src/ui/overlays/BillboardOverlay.cpp
@@ -205,6 +205,7 @@ void BillboardOverlay::replyFinished() {
     QNetworkReply* reply = static_cast<QNetworkReply*>(sender());
     _billboard = reply->readAll();
     _isLoaded = true;
+    reply->deleteLater();
 }
 
 bool BillboardOverlay::findRayIntersection(const glm::vec3& origin, const glm::vec3& direction,
diff --git a/interface/src/ui/overlays/ImageOverlay.cpp b/interface/src/ui/overlays/ImageOverlay.cpp
index d7a6889c05..1ecfc74e44 100644
--- a/interface/src/ui/overlays/ImageOverlay.cpp
+++ b/interface/src/ui/overlays/ImageOverlay.cpp
@@ -66,6 +66,7 @@ void ImageOverlay::replyFinished() {
     _textureImage.loadFromData(rawData);
     _renderImage = true;
     _isLoaded = true;
+    reply->deleteLater();
 }
 
 void ImageOverlay::render(RenderArgs* args) {
diff --git a/libraries/audio/src/AudioConstants.h b/libraries/audio/src/AudioConstants.h
index 91d6db38f7..6c4e582117 100644
--- a/libraries/audio/src/AudioConstants.h
+++ b/libraries/audio/src/AudioConstants.h
@@ -26,8 +26,8 @@ namespace AudioConstants {
     const int NETWORK_FRAME_BYTES_PER_CHANNEL = 512;
     const int NETWORK_FRAME_SAMPLES_PER_CHANNEL = NETWORK_FRAME_BYTES_PER_CHANNEL / sizeof(AudioSample);
     const float NETWORK_FRAME_MSECS = (AudioConstants::NETWORK_FRAME_SAMPLES_PER_CHANNEL
-        / (float) AudioConstants::SAMPLE_RATE) * 1000.0;
-    const unsigned int NETWORK_FRAME_USECS = floorf(NETWORK_FRAME_MSECS * 1000.0);
+        / (float)AudioConstants::SAMPLE_RATE) * 1000.0f;
+    const unsigned int NETWORK_FRAME_USECS = (unsigned int)floorf(NETWORK_FRAME_MSECS * 1000.0f);
     const int MIN_SAMPLE_VALUE = std::numeric_limits<AudioSample>::min();
     const int MAX_SAMPLE_VALUE = std::numeric_limits<AudioSample>::max();
 }
diff --git a/libraries/audio/src/Sound.cpp b/libraries/audio/src/Sound.cpp
index 2608c333d6..54ff61d66a 100644
--- a/libraries/audio/src/Sound.cpp
+++ b/libraries/audio/src/Sound.cpp
@@ -80,6 +80,7 @@ void Sound::downloadFinished(QNetworkReply* reply) {
     }
     
     _isReady = true;
+    reply->deleteLater();
 }
 
 void Sound::downSample(const QByteArray& rawAudioByteArray) {
diff --git a/libraries/avatars/src/AvatarData.cpp b/libraries/avatars/src/AvatarData.cpp
index d5b6c29362..cc45da610f 100644
--- a/libraries/avatars/src/AvatarData.cpp
+++ b/libraries/avatars/src/AvatarData.cpp
@@ -175,11 +175,6 @@ QByteArray AvatarData::toByteArray() {
     // Instantaneous audio loudness (used to drive facial animation)
     memcpy(destinationBuffer, &_headData->_audioLoudness, sizeof(float));
     destinationBuffer += sizeof(float);
-
-    // chat message
-    *destinationBuffer++ = _chatMessage.size();
-    memcpy(destinationBuffer, _chatMessage.data(), _chatMessage.size() * sizeof(char));
-    destinationBuffer += _chatMessage.size() * sizeof(char);
     
     // bitMask of less than byte wide items
     unsigned char bitItems = 0;
@@ -300,11 +295,10 @@ int AvatarData::parseDataAtOffset(const QByteArray& packet, int offset) {
     //     lookAt        = 12
     //     audioLoudness =  4
     // }
-    // + 1 byte for messageSize (0)
     // + 1 byte for pupilSize
     // + 1 byte for numJoints (0)
     // = 53 bytes
-    int minPossibleSize = 53; 
+    int minPossibleSize = 52;
     
     int maxAvailableSize = packet.size() - offset;
     if (minPossibleSize > maxAvailableSize) {
@@ -420,23 +414,6 @@ int AvatarData::parseDataAtOffset(const QByteArray& packet, int offset) {
         _headData->_audioLoudness = audioLoudness;
     } // 4 bytes
     
-    // chat
-    int chatMessageSize = *sourceBuffer++;
-    minPossibleSize += chatMessageSize;
-    if (minPossibleSize > maxAvailableSize) {
-        if (shouldLogError(now)) {
-            qDebug() << "Malformed AvatarData packet before ChatMessage;"
-                << " displayName = '" << _displayName << "'"
-                << " minPossibleSize = " << minPossibleSize 
-                << " maxAvailableSize = " << maxAvailableSize;
-        }
-        return maxAvailableSize;
-    }
-    { // chat payload
-        _chatMessage = string((char*)sourceBuffer, chatMessageSize);
-        sourceBuffer += chatMessageSize * sizeof(char);
-    } // 1 + chatMessageSize bytes
-    
     { // bitFlags and face data
         unsigned char bitItems = *sourceBuffer++;
         
diff --git a/libraries/avatars/src/AvatarData.h b/libraries/avatars/src/AvatarData.h
index 6564d53317..84653ef673 100644
--- a/libraries/avatars/src/AvatarData.h
+++ b/libraries/avatars/src/AvatarData.h
@@ -32,17 +32,17 @@ typedef unsigned long long quint64;
 #include <glm/glm.hpp>
 #include <glm/gtc/quaternion.hpp>
 
-#include <QtCore/QElapsedTimer>
-#include <QtCore/QByteArray>
-#include <QtCore/QHash>
-#include <QtCore/QObject>
-#include <QtCore/QStringList>
-#include <QtCore/QUrl>
-#include <QtCore/QVector>
-#include <QtCore/QVariantMap>
+#include <QByteArray>
+#include <QElapsedTimer>
+#include <QHash>
+#include <QObject>
 #include <QRect>
 #include <QScriptable>
+#include <QStringList>
+#include <QUrl>
 #include <QUuid>
+#include <QVariantMap>
+#include <QVector>
 
 #include <CollisionInfo.h>
 #include <RegisteredMetaTypes.h>
@@ -130,7 +130,6 @@ class AvatarData : public QObject {
     Q_PROPERTY(float bodyYaw READ getBodyYaw WRITE setBodyYaw)
     Q_PROPERTY(float bodyPitch READ getBodyPitch WRITE setBodyPitch)
     Q_PROPERTY(float bodyRoll READ getBodyRoll WRITE setBodyRoll)
-    Q_PROPERTY(QString chatMessage READ getQStringChatMessage WRITE setChatMessage)
 
     Q_PROPERTY(glm::quat orientation READ getOrientation WRITE setOrientation)
     Q_PROPERTY(glm::quat headOrientation READ getHeadOrientation WRITE setHeadOrientation)
@@ -242,12 +241,6 @@ public:
     void setKeyState(KeyState s) { _keyState = s; }
     KeyState keyState() const { return _keyState; }
 
-    // chat message
-    void setChatMessage(const std::string& msg) { _chatMessage = msg; }
-    void setChatMessage(const QString& string) { _chatMessage = string.toLocal8Bit().constData(); }
-    const std::string& setChatMessage() const { return _chatMessage; }
-    QString getQStringChatMessage() { return QString(_chatMessage.data()); }
-
     bool isChatCirclingEnabled() const { return _isChatCirclingEnabled; }
     const HeadData* getHeadData() const { return _headData; }
     const HandData* getHandData() const { return _handData; }
@@ -355,9 +348,6 @@ protected:
     // key state
     KeyState _keyState;
 
-    // chat message
-    std::string _chatMessage;
-
     bool _isChatCirclingEnabled;
     bool _forceFaceshiftConnected;
     bool _hasNewJointRotations; // set in AvatarData, cleared in Avatar
@@ -396,7 +386,6 @@ private:
     AvatarData(const AvatarData&);
     AvatarData& operator= (const AvatarData&);
 };
-
 Q_DECLARE_METATYPE(AvatarData*)
 
 class JointData {
diff --git a/libraries/entities-renderer/src/EntityTreeRenderer.cpp b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
index 4f0f1c80a8..47e9237ddc 100644
--- a/libraries/entities-renderer/src/EntityTreeRenderer.cpp
+++ b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
@@ -145,6 +145,7 @@ QString EntityTreeRenderer::loadScriptContents(const QString& scriptMaybeURLorTe
             } else {
                 qDebug() << "ERROR Loading file:" << url.toString();
             }
+            delete reply;
         }
     }
     
diff --git a/libraries/entities/src/DeleteEntityOperator.cpp b/libraries/entities/src/DeleteEntityOperator.cpp
index 12441e5427..890c301682 100644
--- a/libraries/entities/src/DeleteEntityOperator.cpp
+++ b/libraries/entities/src/DeleteEntityOperator.cpp
@@ -91,13 +91,9 @@ bool DeleteEntityOperator::preRecursion(OctreeElement* element) {
             // If this is the element we're looking for, then ask it to remove the old entity
             // and we can stop searching.
             if (entityTreeElement == details.containingElement) {
-                EntityItemID entityItemID = details.entity->getEntityItemID();
-                EntityItem* theEntity = entityTreeElement->getEntityWithEntityItemID(entityItemID); // find the actual entity
-                assert(theEntity);
-                _tree->trackDeletedEntity(theEntity);
-                entityTreeElement->removeEntityItem(theEntity); // remove it from the element
-                _tree->setContainingElement(entityItemID, NULL); // update or id to element lookup
-                delete theEntity; // now actually delete the entity!
+                EntityItem* theEntity = details.entity;
+                assert(entityTreeElement->removeEntityItem(theEntity)); // remove it from the element
+                _tree->setContainingElement(details.entity->getEntityItemID(), NULL); // update or id to element lookup
                 _foundCount++;
             }
         }
diff --git a/libraries/entities/src/DeleteEntityOperator.h b/libraries/entities/src/DeleteEntityOperator.h
index a3119da0b9..b6e6f9e2ff 100644
--- a/libraries/entities/src/DeleteEntityOperator.h
+++ b/libraries/entities/src/DeleteEntityOperator.h
@@ -14,11 +14,13 @@
 
 class EntityToDeleteDetails {
 public:
-    const EntityItem* entity;
+    EntityItem* entity;
     AACube cube;
     EntityTreeElement* containingElement;
 };
 
+typedef QSet<EntityToDeleteDetails> RemovedEntities;
+
 inline uint qHash(const EntityToDeleteDetails& a, uint seed) {
     return qHash(a.entity->getEntityItemID(), seed);
 }
@@ -36,9 +38,11 @@ public:
     void addEntityIDToDeleteList(const EntityItemID& searchEntityID);
     virtual bool preRecursion(OctreeElement* element);
     virtual bool postRecursion(OctreeElement* element);
+
+    const RemovedEntities& getEntities() const { return _entitiesToDelete; }
 private:
     EntityTree* _tree;
-    QSet<EntityToDeleteDetails> _entitiesToDelete;
+    RemovedEntities _entitiesToDelete;
     quint64 _changeTime;
     int _foundCount;
     int _lookingCount;
diff --git a/libraries/entities/src/EntityItem.cpp b/libraries/entities/src/EntityItem.cpp
index 3a2b8c64b1..a744d39f05 100644
--- a/libraries/entities/src/EntityItem.cpp
+++ b/libraries/entities/src/EntityItem.cpp
@@ -1019,7 +1019,6 @@ void EntityItem::recalculateCollisionShape() {
 }
 
 const float MIN_POSITION_DELTA = 0.0001f;
-const float MIN_DIMENSION_DELTA = 0.0001f;
 const float MIN_ALIGNMENT_DOT = 0.9999f;
 const float MIN_MASS_DELTA = 0.001f;
 const float MIN_VELOCITY_DELTA = 0.025f;
@@ -1045,17 +1044,17 @@ void EntityItem::updatePositionInMeters(const glm::vec3& value) {
 }
 
 void EntityItem::updateDimensions(const glm::vec3& value) { 
-    if (glm::distance(_dimensions, value) * (float)TREE_SCALE > MIN_DIMENSION_DELTA) {
-        _dimensions = value; 
+    if (_dimensions != value) {
+        _dimensions = glm::abs(value);
         recalculateCollisionShape();
         _dirtyFlags |= (EntityItem::DIRTY_SHAPE | EntityItem::DIRTY_MASS);
     }
 }
 
 void EntityItem::updateDimensionsInMeters(const glm::vec3& value) { 
-    glm::vec3 dimensions = value / (float) TREE_SCALE;
-    if (glm::distance(_dimensions, dimensions) * (float)TREE_SCALE > MIN_DIMENSION_DELTA) {
-        _dimensions = dimensions; 
+    glm::vec3 dimensions = glm::abs(value) / (float) TREE_SCALE;
+    if (_dimensions != dimensions) {
+        _dimensions = dimensions;
         recalculateCollisionShape();
         _dirtyFlags |= (EntityItem::DIRTY_SHAPE | EntityItem::DIRTY_MASS);
     }
diff --git a/libraries/entities/src/EntitySimulation.cpp b/libraries/entities/src/EntitySimulation.cpp
index 09f75c9ebf..f7d6c55803 100644
--- a/libraries/entities/src/EntitySimulation.cpp
+++ b/libraries/entities/src/EntitySimulation.cpp
@@ -38,6 +38,7 @@ void EntitySimulation::updateEntities(QSet<EntityItem*>& entitiesToDelete) {
     _entitiesToDelete.clear();
 }
 
+// private
 void EntitySimulation::expireMortalEntities(const quint64& now) {
     if (now > _nextExpiry) {
         // only search for expired entities if we expect to find one
@@ -63,6 +64,7 @@ void EntitySimulation::expireMortalEntities(const quint64& now) {
     }
 }
 
+// private
 void EntitySimulation::callUpdateOnEntitiesThatNeedIt(const quint64& now) {
     PerformanceTimer perfTimer("updatingEntities");
     QSet<EntityItem*>::iterator itemItr = _updateableEntities.begin();
@@ -79,6 +81,7 @@ void EntitySimulation::callUpdateOnEntitiesThatNeedIt(const quint64& now) {
     }
 }
 
+// private
 void EntitySimulation::sortEntitiesThatMoved() {
     // NOTE: this is only for entities that have been moved by THIS EntitySimulation.
     // External changes to entity position/shape are expected to be sorted outside of the EntitySimulation.
diff --git a/libraries/entities/src/EntitySimulation.h b/libraries/entities/src/EntitySimulation.h
index a32a1226c7..dee6b1c43a 100644
--- a/libraries/entities/src/EntitySimulation.h
+++ b/libraries/entities/src/EntitySimulation.h
@@ -33,9 +33,12 @@ const int DIRTY_SIMULATION_FLAGS =
 
 class EntitySimulation {
 public:
-    EntitySimulation() : _entityTree(NULL) { }
+    EntitySimulation() : _mutex(QMutex::Recursive), _entityTree(NULL) { }
     virtual ~EntitySimulation() { setEntityTree(NULL); }
 
+    void lock() { _mutex.lock(); }
+    void unlock() { _mutex.unlock(); }
+
     /// \param tree pointer to EntityTree which is stored internally
     void setEntityTree(EntityTree* tree);
 
@@ -80,6 +83,8 @@ protected:
     void callUpdateOnEntitiesThatNeedIt(const quint64& now);
     void sortEntitiesThatMoved();
 
+    QMutex _mutex;
+
     // back pointer to EntityTree structure
     EntityTree* _entityTree;
 
diff --git a/libraries/entities/src/EntityTree.cpp b/libraries/entities/src/EntityTree.cpp
index 73d944b084..580fed8790 100644
--- a/libraries/entities/src/EntityTree.cpp
+++ b/libraries/entities/src/EntityTree.cpp
@@ -15,7 +15,6 @@
 #include "EntitySimulation.h"
 
 #include "AddEntityOperator.h"
-#include "DeleteEntityOperator.h"
 #include "MovingEntitiesOperator.h"
 #include "UpdateEntityOperator.h"
 
@@ -40,7 +39,9 @@ EntityTreeElement* EntityTree::createNewElement(unsigned char * octalCode) {
 void EntityTree::eraseAllOctreeElements(bool createNewRoot) {
     // this would be a good place to clean up our entities...
     if (_simulation) {
+        _simulation->lock();
         _simulation->clearEntities();
+        _simulation->unlock();
     }
     foreach (EntityTreeElement* element, _entityToElementMap) {
         element->cleanupEntities();
@@ -84,7 +85,9 @@ void EntityTree::postAddEntity(EntityItem* entity) {
     assert(entity);
     // check to see if we need to simulate this entity..
     if (_simulation) {
+        _simulation->lock();
         _simulation->addEntity(entity);
+        _simulation->unlock();
     }
     _isDirty = true;
     emit addingEntity(entity->getEntityItemID());
@@ -141,7 +144,9 @@ bool EntityTree::updateEntityWithElement(EntityItem* entity, const EntityItemPro
         if (newFlags) {
             if (_simulation) { 
                 if (newFlags & DIRTY_SIMULATION_FLAGS) {
+                    _simulation->lock();
                     _simulation->entityChanged(entity);
+                    _simulation->unlock();
                 }
             } else {
                 // normally the _simulation clears ALL updateFlags, but since there is none we do it explicitly
@@ -204,21 +209,6 @@ EntityItem* EntityTree::addEntity(const EntityItemID& entityID, const EntityItem
     return result;
 }
 
-
-void EntityTree::trackDeletedEntity(EntityItem* entity) {
-    if (_simulation) {
-        _simulation->removeEntity(entity);
-    }
-    // this is only needed on the server to send delete messages for recently deleted entities to the viewers
-    if (getIsServer()) {
-        // set up the deleted entities ID
-        quint64 deletedAt = usecTimestampNow();
-        _recentlyDeletedEntitiesLock.lockForWrite();
-        _recentlyDeletedEntityItemIDs.insert(deletedAt, entity->getEntityItemID().id);
-        _recentlyDeletedEntitiesLock.unlock();
-    }
-}
-
 void EntityTree::emitEntityScriptChanging(const EntityItemID& entityItemID) {
     emit entityScriptChanging(entityItemID);
 }
@@ -231,7 +221,9 @@ void EntityTree::setSimulation(EntitySimulation* simulation) {
     if (_simulation && _simulation != simulation) {
         // It's important to clearEntities() on the simulation since taht will update each
         // EntityItem::_simulationState correctly so as to not confuse the next _simulation.
+        _simulation->lock();
         _simulation->clearEntities();
+        _simulation->unlock();
     }
     _simulation = simulation;
 }
@@ -242,6 +234,7 @@ void EntityTree::deleteEntity(const EntityItemID& entityID) {
     // NOTE: callers must lock the tree before using this method
     DeleteEntityOperator theOperator(this, entityID);
     recurseTreeWithOperator(&theOperator);
+    processRemovedEntities(theOperator);
     _isDirty = true;
 }
 
@@ -255,9 +248,36 @@ void EntityTree::deleteEntities(QSet<EntityItemID> entityIDs) {
     }
 
     recurseTreeWithOperator(&theOperator);
+    processRemovedEntities(theOperator);
     _isDirty = true;
 }
 
+void EntityTree::processRemovedEntities(const DeleteEntityOperator& theOperator) {
+    const RemovedEntities& entities = theOperator.getEntities();
+    if (_simulation) {
+        _simulation->lock();
+    }
+    foreach(const EntityToDeleteDetails& details, entities) {
+        EntityItem* theEntity = details.entity;
+
+        if (getIsServer()) {
+            // set up the deleted entities ID
+            quint64 deletedAt = usecTimestampNow();
+            _recentlyDeletedEntitiesLock.lockForWrite();
+            _recentlyDeletedEntityItemIDs.insert(deletedAt, theEntity->getEntityItemID().id);
+            _recentlyDeletedEntitiesLock.unlock();
+        }
+
+        if (_simulation) {
+            _simulation->removeEntity(theEntity);
+        }
+        delete theEntity; // now actually delete the entity!
+    }
+    if (_simulation) {
+        _simulation->unlock();
+    }
+}
+
 /// This method is used to find and fix entity IDs that are shifting from creator token based to known ID based entity IDs. 
 /// This should only be used on a client side (viewing) tree. The typical usage is that a local editor has been creating 
 /// entities in the local tree, those entities have creatorToken based entity IDs. But those entity edits are also sent up to
@@ -592,7 +612,9 @@ void EntityTree::releaseSceneEncodeData(OctreeElementExtraEncodeData* extraEncod
 
 void EntityTree::entityChanged(EntityItem* entity) {
     if (_simulation) {
+        _simulation->lock();
         _simulation->entityChanged(entity);
+        _simulation->unlock();
     }
 }
 
@@ -600,7 +622,9 @@ void EntityTree::update() {
     if (_simulation) {
         lockForWrite();
         QSet<EntityItem*> entitiesToDelete;
+        _simulation->lock();
         _simulation->updateEntities(entitiesToDelete);
+        _simulation->unlock();
         if (entitiesToDelete.size() > 0) {
             // translate into list of ID's
             QSet<EntityItemID> idsToDelete;
diff --git a/libraries/entities/src/EntityTree.h b/libraries/entities/src/EntityTree.h
index cfd08c3b5c..e8c8a93165 100644
--- a/libraries/entities/src/EntityTree.h
+++ b/libraries/entities/src/EntityTree.h
@@ -16,6 +16,7 @@
 
 #include <Octree.h>
 #include "EntityTreeElement.h"
+#include "DeleteEntityOperator.h"
 
 
 class Model;
@@ -146,8 +147,6 @@ public:
 
     void entityChanged(EntityItem* entity);
 
-    void trackDeletedEntity(EntityItem* entity);
-
     void emitEntityScriptChanging(const EntityItemID& entityItemID);
 
     void setSimulation(EntitySimulation* simulation);
@@ -160,6 +159,7 @@ signals:
 
 private:
 
+    void processRemovedEntities(const DeleteEntityOperator& theOperator);
     bool updateEntityWithElement(EntityItem* entity, const EntityItemProperties& properties, 
             EntityTreeElement* containingElement);
     static bool findNearPointOperation(OctreeElement* element, void* extraData);
diff --git a/libraries/networking/src/DomainHandler.cpp b/libraries/networking/src/DomainHandler.cpp
index 126ef27414..e4f31e666e 100644
--- a/libraries/networking/src/DomainHandler.cpp
+++ b/libraries/networking/src/DomainHandler.cpp
@@ -240,6 +240,7 @@ void DomainHandler::settingsRequestFinished() {
             requestDomainSettings();
         }        
     }
+    settingsReply->deleteLater();
 }
 
 void DomainHandler::parseDTLSRequirementPacket(const QByteArray& dtlsRequirementPacket) {
diff --git a/libraries/networking/src/PacketHeaders.cpp b/libraries/networking/src/PacketHeaders.cpp
index d5c53f8fcf..b1790ac4ce 100644
--- a/libraries/networking/src/PacketHeaders.cpp
+++ b/libraries/networking/src/PacketHeaders.cpp
@@ -57,7 +57,7 @@ PacketVersion versionForPacketType(PacketType type) {
         case PacketTypeInjectAudio:
             return 1;
         case PacketTypeAvatarData:
-            return 3;
+            return 4;
         case PacketTypeAvatarIdentity:
             return 1;
         case PacketTypeEnvironmentData:
diff --git a/libraries/networking/src/ResourceCache.cpp b/libraries/networking/src/ResourceCache.cpp
index 5bb327fe63..4b769c9a28 100644
--- a/libraries/networking/src/ResourceCache.cpp
+++ b/libraries/networking/src/ResourceCache.cpp
@@ -67,13 +67,27 @@ QSharedPointer<Resource> ResourceCache::getResource(const QUrl& url, const QUrl&
         _resources.insert(url, resource);
         
     } else {
-        _unusedResources.remove(resource->getLRUKey());
+        removeUnusedResource(resource);
     }
     return resource;
 }
 
 void ResourceCache::addUnusedResource(const QSharedPointer<Resource>& resource) {
+    static const int BYTES_PER_MEGABYTES = 1024 * 1024;
     const int RETAINED_RESOURCE_COUNT = 50;
+    const int RETAINED_RESOURCE_SIZE = 100 * BYTES_PER_MEGABYTES;
+    
+    while (_unusedResourcesTotalBytes + resource->getBytesTotal() > RETAINED_RESOURCE_SIZE &&
+           !_unusedResources.empty()) {
+        // unload the oldest resource
+        QMap<int, QSharedPointer<Resource> >::iterator it = _unusedResources.begin();
+        
+        _unusedResourcesTotalBytes -= it.value()->getBytesTotal();
+        it.value()->setCache(NULL);
+        _unusedResources.erase(it);
+    }
+    
+    
     if (_unusedResources.size() > RETAINED_RESOURCE_COUNT) {
         // unload the oldest resource
         QMap<int, QSharedPointer<Resource> >::iterator it = _unusedResources.begin();
@@ -82,6 +96,14 @@ void ResourceCache::addUnusedResource(const QSharedPointer<Resource>& resource)
     }
     resource->setLRUKey(++_lastLRUKey);
     _unusedResources.insert(resource->getLRUKey(), resource);
+    _unusedResourcesTotalBytes += resource->getBytesTotal();
+}
+
+void ResourceCache::removeUnusedResource(const QSharedPointer<Resource>& resource) {
+    if (_unusedResources.contains(resource->getLRUKey())) {
+        _unusedResources.remove(resource->getLRUKey());
+        _unusedResourcesTotalBytes -= resource->getBytesTotal();
+    }
 }
 
 void ResourceCache::attemptRequest(Resource* resource) {
diff --git a/libraries/networking/src/ResourceCache.h b/libraries/networking/src/ResourceCache.h
index e1b6327652..0a4121ca5e 100644
--- a/libraries/networking/src/ResourceCache.h
+++ b/libraries/networking/src/ResourceCache.h
@@ -45,7 +45,8 @@ public:
     void refresh(const QUrl& url);
 
 protected:
-
+    
+    qint64 _unusedResourcesTotalBytes = 0;
     QMap<int, QSharedPointer<Resource> > _unusedResources;
 
     /// Loads a resource from the specified URL.
@@ -58,8 +59,9 @@ protected:
     /// Creates a new resource.
     virtual QSharedPointer<Resource> createResource(const QUrl& url,
         const QSharedPointer<Resource>& fallback, bool delayLoad, const void* extra) = 0;
-
+    
     void addUnusedResource(const QSharedPointer<Resource>& resource);
+    void removeUnusedResource(const QSharedPointer<Resource>& resource);
     
     static void attemptRequest(Resource* resource);
     static void requestCompleted(Resource* resource);
diff --git a/libraries/physics/src/PhysicsEngine.cpp b/libraries/physics/src/PhysicsEngine.cpp
index edff3f8291..4129f1c7b0 100644
--- a/libraries/physics/src/PhysicsEngine.cpp
+++ b/libraries/physics/src/PhysicsEngine.cpp
@@ -169,7 +169,7 @@ void PhysicsEngine::init(EntityEditPacketSender* packetSender) {
         _collisionDispatcher = new btCollisionDispatcher(_collisionConfig);
         _broadphaseFilter = new btDbvtBroadphase();
         _constraintSolver = new btSequentialImpulseConstraintSolver;
-        _dynamicsWorld = new ThreadSafeDynamicsWorld(_collisionDispatcher, _broadphaseFilter, _constraintSolver, _collisionConfig, _entityTree);
+        _dynamicsWorld = new ThreadSafeDynamicsWorld(_collisionDispatcher, _broadphaseFilter, _constraintSolver, _collisionConfig);
 
         // default gravity of the world is zero, so each object must specify its own gravity
         // TODO: set up gravity zones
@@ -200,13 +200,14 @@ void PhysicsEngine::init(EntityEditPacketSender* packetSender) {
 const float FIXED_SUBSTEP = 1.0f / 60.0f;
 
 void PhysicsEngine::stepSimulation() {
+    lock();
     // NOTE: the grand order of operations is:
     // (1) relay incoming changes
     // (2) step simulation
     // (3) synchronize outgoing motion states
     // (4) send outgoing packets
 
-    // this is step (1)
+    // This is step (1).
     relayIncomingChangesToSimulation();
 
     const int MAX_NUM_SUBSTEPS = 4;
@@ -215,9 +216,24 @@ void PhysicsEngine::stepSimulation() {
     _clock.reset();
     float timeStep = btMin(dt, MAX_TIMESTEP);
 
-    // steps (2) and (3) are performed by ThreadSafeDynamicsWorld::stepSimulation())
+    // This is step (2).
     int numSubSteps = _dynamicsWorld->stepSimulation(timeStep, MAX_NUM_SUBSTEPS, FIXED_SUBSTEP);
     _frameCount += (uint32_t)numSubSteps;
+    unlock();
+
+    // This is step (3) which is done outside of stepSimulation() so we can lock _entityTree.
+    //
+    // Unfortunately we have to unlock the simulation (above) before we try to lock the _entityTree
+    // to avoid deadlock -- the _entityTree may try to lock its EntitySimulation (from which this 
+    // PhysicsEngine derives) when updating/adding/deleting entities so we need to wait for our own
+    // lock on the tree before we re-lock ourselves.
+    //
+    // TODO: untangle these lock sequences.
+    _entityTree->lockForWrite();
+    lock();
+    _dynamicsWorld->synchronizeMotionStates();
+    unlock();
+    _entityTree->unlock();
 }
 
 // Bullet collision flags are as follows:
diff --git a/libraries/physics/src/ThreadSafeDynamicsWorld.cpp b/libraries/physics/src/ThreadSafeDynamicsWorld.cpp
index e70bdc7210..e204ae9e7f 100644
--- a/libraries/physics/src/ThreadSafeDynamicsWorld.cpp
+++ b/libraries/physics/src/ThreadSafeDynamicsWorld.cpp
@@ -15,8 +15,6 @@
  * Copied and modified from btDiscreteDynamicsWorld.cpp by AndrewMeadows on 2014.11.12.
  * */
 
-#include <EntityTree.h>
-
 #include "ThreadSafeDynamicsWorld.h"
 
 #ifdef USE_BULLET_PHYSICS
@@ -24,17 +22,8 @@ ThreadSafeDynamicsWorld::ThreadSafeDynamicsWorld(
         btDispatcher* dispatcher,
         btBroadphaseInterface* pairCache,
         btConstraintSolver* constraintSolver,
-        btCollisionConfiguration* collisionConfiguration,
-        EntityTree* entities)
+        btCollisionConfiguration* collisionConfiguration)
     :   btDiscreteDynamicsWorld(dispatcher, pairCache, constraintSolver, collisionConfiguration) {
-    assert(entities);
-    _entities = entities;
-}
-
-void ThreadSafeDynamicsWorld::synchronizeMotionStates() {
-    _entities->lockForWrite();
-    btDiscreteDynamicsWorld::synchronizeMotionStates();
-    _entities->unlock();
 }
 
 int	ThreadSafeDynamicsWorld::stepSimulation( btScalar timeStep, int maxSubSteps, btScalar fixedTimeStep) {
@@ -82,10 +71,15 @@ int	ThreadSafeDynamicsWorld::stepSimulation( btScalar timeStep, int maxSubSteps,
 		}
 	}
 
-    // We only sync motion states once at the end of all substeps.  
-    // This is to avoid placing multiple, repeated thread locks on _entities.
-    synchronizeMotionStates();
+    // NOTE: We do NOT call synchronizeMotionState() after each substep (to avoid multiple locks on the
+    // object data outside of the physics engine).  A consequence of this is that the transforms of the
+    // external objects only ever update at the end of the full step.
+
+    // NOTE: We do NOT call synchronizeMotionStates() here.  Instead it is called by an external class
+    // that knows how to lock threads correctly.
+
 	clearForces();
-	return subSteps;
+
+    return subSteps;
 }
 #endif // USE_BULLET_PHYSICS
diff --git a/libraries/physics/src/ThreadSafeDynamicsWorld.h b/libraries/physics/src/ThreadSafeDynamicsWorld.h
index 3f3bc2517b..64d5413c56 100644
--- a/libraries/physics/src/ThreadSafeDynamicsWorld.h
+++ b/libraries/physics/src/ThreadSafeDynamicsWorld.h
@@ -21,8 +21,6 @@
 #ifdef USE_BULLET_PHYSICS
 #include <BulletDynamics/Dynamics/btDiscreteDynamicsWorld.h>
 
-class EntityTree;
-
 ATTRIBUTE_ALIGNED16(class) ThreadSafeDynamicsWorld : public btDiscreteDynamicsWorld {
 public:
     BT_DECLARE_ALIGNED_ALLOCATOR();
@@ -31,20 +29,15 @@ public:
             btDispatcher* dispatcher,
             btBroadphaseInterface* pairCache,
             btConstraintSolver* constraintSolver,
-            btCollisionConfiguration* collisionConfiguration,
-            EntityTree* entities);
+            btCollisionConfiguration* collisionConfiguration);
 
     // virtual overrides from btDiscreteDynamicsWorld
     int stepSimulation( btScalar timeStep, int maxSubSteps=1, btScalar fixedTimeStep=btScalar(1.)/btScalar(60.));
-    void synchronizeMotionStates();
 
     // btDiscreteDynamicsWorld::m_localTime is the portion of real-time that has not yet been simulated
     // but is used for MotionState::setWorldTransform() extrapolation (a feature that Bullet uses to provide 
     // smoother rendering of objects when the physics simulation loop is ansynchronous to the render loop).
     float getLocalTimeAccumulation() const { return m_localTime; }
-
-private:
-    EntityTree* _entities;
 };
 
 #else // USE_BULLET_PHYSICS
diff --git a/libraries/script-engine/src/ScriptEngine.cpp b/libraries/script-engine/src/ScriptEngine.cpp
index 5f03e771ea..9450d99cf9 100644
--- a/libraries/script-engine/src/ScriptEngine.cpp
+++ b/libraries/script-engine/src/ScriptEngine.cpp
@@ -194,6 +194,8 @@ void ScriptEngine::handleScriptDownload() {
         qDebug() << "ERROR Loading file:" << reply->url().toString();
         emit errorLoadingScript(_fileNameString);
     }
+    
+    reply->deleteLater();
 }
 
 void ScriptEngine::init() {
@@ -605,6 +607,7 @@ void ScriptEngine::include(const QString& includeFile) {
         QObject::connect(reply, SIGNAL(finished()), &loop, SLOT(quit()));
         loop.exec();
         includeContents = reply->readAll();
+        reply->deleteLater();
     } else {
 #ifdef _WIN32
         QString fileName = url.toString();
diff --git a/libraries/script-engine/src/XMLHttpRequestClass.cpp b/libraries/script-engine/src/XMLHttpRequestClass.cpp
index dec20dface..a756b3fe8f 100644
--- a/libraries/script-engine/src/XMLHttpRequestClass.cpp
+++ b/libraries/script-engine/src/XMLHttpRequestClass.cpp
@@ -332,7 +332,7 @@ void XMLHttpRequestClass::abortRequest() {
     if (_reply) {
         disconnectFromReply(_reply);
         _reply->abort();
-        delete _reply;
+        _reply->deleteLater();
         _reply = NULL;
     }
 
diff --git a/tests/octree/src/OctreeTests.cpp b/tests/octree/src/OctreeTests.cpp
index 05d6cb593d..4fc543d5d3 100644
--- a/tests/octree/src/OctreeTests.cpp
+++ b/tests/octree/src/OctreeTests.cpp
@@ -802,7 +802,7 @@ void OctreeTests::propertyFlagsTests(bool verbose) {
             qDebug() << "fill encoded byte array with extra garbage (as if it was bitstream with more content)";
         }
         QByteArray extraContent;
-        extraContent.fill(0xba, 10);
+        extraContent.fill(0xbaU, 10);
         encoded.append(extraContent);
 
         if (verbose) {
diff --git a/tools/scribe/src/TextTemplate.cpp b/tools/scribe/src/TextTemplate.cpp
index 5d10e55e3f..752d4a37d8 100755
--- a/tools/scribe/src/TextTemplate.cpp
+++ b/tools/scribe/src/TextTemplate.cpp
@@ -837,7 +837,7 @@ int TextTemplate::evalBlockGeneration(std::ostream& dst, const BlockPointer& blo
             if (block->command.arguments.size()) {
                 // THe actual value of the var defined sneeds to be evaluated:
                 String val;
-                for (int t = 1; t < block->command.arguments.size(); t++) {
+                for (unsigned int t = 1; t < block->command.arguments.size(); t++) {
                     // detect if a param is a var
                     int len = block->command.arguments[t].length();
                     if ((block->command.arguments[t][0] == Tag::VAR)