diff --git a/examples/SharedMemory/PhysicsClient.h b/examples/SharedMemory/PhysicsClient.h
index 785e01e7b..7c97996df 100644
--- a/examples/SharedMemory/PhysicsClient.h
+++ b/examples/SharedMemory/PhysicsClient.h
@@ -73,6 +73,12 @@ public:
 	virtual void setTimeOut(double timeOutInSeconds) = 0;
 	virtual double getTimeOut() const  = 0;
 
+	virtual bool getCachedUserData(int bodyUniqueId, int linkIndex, int userDataId, struct b3UserDataValue &valueOut) const = 0;
+	virtual int getCachedUserDataId(int bodyUniqueId, int linkIndex, const char *key) const = 0;
+	virtual int getNumUserData(int bodyUniqueId, int linkIndex) const = 0;
+	virtual void getUserDataInfo(int bodyUniqueId, int linkIndex, int userDataIndex, const char **keyOut, int *userDataIdOut) const = 0;
 };
 
+
+
 #endif  // BT_PHYSICS_CLIENT_API_H
diff --git a/examples/SharedMemory/PhysicsClientC_API.cpp b/examples/SharedMemory/PhysicsClientC_API.cpp
index afa1da448..0dc931a93 100644
--- a/examples/SharedMemory/PhysicsClientC_API.cpp
+++ b/examples/SharedMemory/PhysicsClientC_API.cpp
@@ -1414,6 +1414,20 @@ B3_SHARED_API void b3CreateMultiBodyUseMaximalCoordinates(b3SharedMemoryCommandH
 	}
 }
 
+
+B3_SHARED_API	void b3CreateMultiBodySetFlags(b3SharedMemoryCommandHandle commandHandle, int flags)
+{
+	struct SharedMemoryCommand* command = (struct SharedMemoryCommand*) commandHandle;
+    b3Assert(command);
+    b3Assert(command->m_type == CMD_CREATE_MULTI_BODY);
+	if (command->m_type==CMD_CREATE_MULTI_BODY)
+	{
+		command->m_updateFlags |= MULT_BODY_HAS_FLAGS;
+		command->m_createMultiBodyArgs.m_flags = flags;
+	}
+	
+}
+
 B3_SHARED_API int b3GetStatusMultiBodyUniqueId(b3SharedMemoryStatusHandle statusHandle)
 {
 	const SharedMemoryStatus* status = (const SharedMemoryStatus* ) statusHandle;
@@ -2777,6 +2791,103 @@ B3_SHARED_API	b3SharedMemoryCommandHandle b3InitSyncBodyInfoCommand(b3PhysicsCli
 	return (b3SharedMemoryCommandHandle) command;
 }
 
+B3_SHARED_API  b3SharedMemoryCommandHandle b3InitSyncUserDataCommand(b3PhysicsClientHandle physClient) {
+	PhysicsClient* cl = (PhysicsClient* ) physClient;
+	b3Assert(cl);
+	b3Assert(cl->canSubmitCommand());
+	struct SharedMemoryCommand* command = cl->getAvailableSharedMemoryCommand();
+	b3Assert(command);
+
+	command->m_type = CMD_SYNC_USER_DATA;
+	return (b3SharedMemoryCommandHandle) command;
+}
+
+B3_SHARED_API  b3SharedMemoryCommandHandle b3InitAddUserDataCommand(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex, const char* key, UserDataValueType valueType, int valueLength, const void *valueData) {
+	PhysicsClient* cl = (PhysicsClient* ) physClient;
+	b3Assert(strlen(key) < MAX_USER_DATA_KEY_LENGTH);
+	b3Assert(cl);
+	b3Assert(cl->canSubmitCommand());
+	struct SharedMemoryCommand* command = cl->getAvailableSharedMemoryCommand();
+	b3Assert(command);
+
+
+	command->m_type = CMD_ADD_USER_DATA;
+	command->m_addUserDataRequestArgs.m_bodyUniqueId = bodyUniqueId;
+	command->m_addUserDataRequestArgs.m_linkIndex = linkIndex;
+	command->m_addUserDataRequestArgs.m_valueType = valueType;
+	command->m_addUserDataRequestArgs.m_valueLength = valueLength;
+	strcpy(command->m_addUserDataRequestArgs.m_key, key);
+	cl->uploadBulletFileToSharedMemory((const char *)valueData, valueLength);
+
+	return (b3SharedMemoryCommandHandle) command;
+}
+
+B3_SHARED_API  b3SharedMemoryCommandHandle b3InitRemoveUserDataCommand(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex, int userDataId) {
+	PhysicsClient* cl = (PhysicsClient* ) physClient;
+	b3Assert(cl);
+	b3Assert(cl->canSubmitCommand());
+	struct SharedMemoryCommand* command = cl->getAvailableSharedMemoryCommand();
+	b3Assert(command);
+
+	command->m_type = CMD_REMOVE_USER_DATA;
+	command->m_removeUserDataRequestArgs.m_bodyUniqueId = bodyUniqueId;
+	command->m_removeUserDataRequestArgs.m_linkIndex = linkIndex;
+	command->m_removeUserDataRequestArgs.m_userDataId = userDataId;
+
+	return (b3SharedMemoryCommandHandle) command;
+}
+
+B3_SHARED_API int b3GetUserData(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex, int userDataId, struct b3UserDataValue *valueOut)
+{
+	PhysicsClient* cl = (PhysicsClient*)physClient;
+	if (cl)
+	{
+		return cl->getCachedUserData(bodyUniqueId, linkIndex, userDataId, *valueOut);
+	}
+	return false;
+}
+
+B3_SHARED_API int b3GetUserDataId(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex, const char *key)
+{
+	PhysicsClient* cl = (PhysicsClient*)physClient;
+	if (cl)
+	{
+		return cl->getCachedUserDataId(bodyUniqueId, linkIndex, key);
+	}
+	return -1;
+}
+
+B3_SHARED_API int b3GetUserDataIdFromStatus(b3SharedMemoryStatusHandle statusHandle)
+{
+	const SharedMemoryStatus* status = (const SharedMemoryStatus*)statusHandle;
+	if (status)
+	{
+		btAssert(status->m_type == CMD_ADD_USER_DATA_COMPLETED);
+		return status->m_userDataResponseArgs.m_userDataGlobalId.m_userDataId;
+	}
+	return -1;
+}
+
+B3_SHARED_API int b3GetNumUserData(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex)
+{
+	PhysicsClient* cl = (PhysicsClient*)physClient;
+	if (cl)
+	{
+		return cl->getNumUserData(bodyUniqueId, linkIndex);
+	}
+	return 0;
+}
+
+B3_SHARED_API void b3GetUserDataInfo(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex, int userDataIndex, const char **keyOut, int *userDataIdOut)
+{
+	PhysicsClient* cl = (PhysicsClient*)physClient;
+	if (cl)
+	{
+		cl->getUserDataInfo(bodyUniqueId, linkIndex, userDataIndex, keyOut, userDataIdOut);
+	}
+}
+
+
 B3_SHARED_API	b3SharedMemoryCommandHandle b3InitRequestDebugLinesCommand(b3PhysicsClientHandle physClient, int debugMode)
 {
     PhysicsClient* cl = (PhysicsClient* ) physClient;
diff --git a/examples/SharedMemory/PhysicsClientC_API.h b/examples/SharedMemory/PhysicsClientC_API.h
index 3c23c2003..1776c1da6 100644
--- a/examples/SharedMemory/PhysicsClientC_API.h
+++ b/examples/SharedMemory/PhysicsClientC_API.h
@@ -113,6 +113,17 @@ B3_SHARED_API	int	b3ComputeDofCount(b3PhysicsClientHandle physClient, int bodyUn
 ///given a body and joint index, return the joint information. See b3JointInfo in SharedMemoryPublic.h
 B3_SHARED_API	int	b3GetJointInfo(b3PhysicsClientHandle physClient, int bodyUniqueId, int jointIndex, struct b3JointInfo* info);
 
+///user data handling
+B3_SHARED_API b3SharedMemoryCommandHandle b3InitSyncUserDataCommand(b3PhysicsClientHandle physClient);
+B3_SHARED_API b3SharedMemoryCommandHandle b3InitAddUserDataCommand(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex, const char* key, enum UserDataValueType valueType, int valueLength, const void *valueData);
+B3_SHARED_API b3SharedMemoryCommandHandle b3InitRemoveUserDataCommand(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex, int userDataId);
+
+B3_SHARED_API int b3GetUserData(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex, int userDataId, struct b3UserDataValue *valueOut);
+B3_SHARED_API int b3GetUserDataId(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex, const char *key);
+B3_SHARED_API int b3GetUserDataIdFromStatus(b3SharedMemoryStatusHandle statusHandle);
+B3_SHARED_API int b3GetNumUserData(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex);
+B3_SHARED_API void b3GetUserDataInfo(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex, int userDataIndex, const char **keyOut, int *userDataIdOut);
+
 B3_SHARED_API	b3SharedMemoryCommandHandle b3GetDynamicsInfoCommandInit(b3PhysicsClientHandle physClient, int bodyUniqueId, int linkIndex);
 ///given a body unique id and link index, return the dynamics information. See b3DynamicsInfo in SharedMemoryPublic.h
 B3_SHARED_API	int b3GetDynamicsInfo(b3SharedMemoryStatusHandle statusHandle, struct b3DynamicsInfo* info);
@@ -466,6 +477,8 @@ B3_SHARED_API	int b3CreateMultiBodyLink(b3SharedMemoryCommandHandle commandHandl
 
 //useMaximalCoordinates are disabled by default, enabling them is experimental and not fully supported yet
 B3_SHARED_API	void b3CreateMultiBodyUseMaximalCoordinates(b3SharedMemoryCommandHandle commandHandle);
+B3_SHARED_API	void b3CreateMultiBodySetFlags(b3SharedMemoryCommandHandle commandHandle, int flags);
+
 
 //int b3CreateMultiBodyAddLink(b3SharedMemoryCommandHandle commandHandle, int jointType, int parentLinkIndex, double linkMass, int linkCollisionShapeUnique, int linkVisualShapeUniqueId);
 
diff --git a/examples/SharedMemory/PhysicsClientSharedMemory.cpp b/examples/SharedMemory/PhysicsClientSharedMemory.cpp
index c78eff91c..0f2ec78c0 100644
--- a/examples/SharedMemory/PhysicsClientSharedMemory.cpp
+++ b/examples/SharedMemory/PhysicsClientSharedMemory.cpp
@@ -11,16 +11,34 @@
 #include "../../Extras/Serialize/BulletFileLoader/autogenerated/bullet.h"
 #include "SharedMemoryBlock.h"
 #include "BodyJointInfoUtility.h"
+#include "SharedMemoryUserData.h"
 
 
 
+struct UserDataCache 
+{
+	btHashMap<btHashInt, SharedMemoryUserData> m_userDataMap;
+	btHashMap<btHashString, int> m_keyToUserDataIdMap;
 
+	UserDataCache()
+	{
+	}
+	~UserDataCache() 
+	{
+	}
+};
 
 struct BodyJointInfoCache
 {
 	std::string m_baseName;
 	b3AlignedObjectArray<b3JointInfo> m_jointInfo;
 	std::string m_bodyName;
+	// Joint index -> user data.
+	btHashMap<btHashInt, UserDataCache> m_jointToUserDataMap;
+
+	~BodyJointInfoCache() 
+	{
+	}
 };
 
 struct PhysicsClientSharedMemoryInternalData {
@@ -28,32 +46,34 @@ struct PhysicsClientSharedMemoryInternalData {
 	bool	m_ownsSharedMemory;
     SharedMemoryBlock* m_testBlock1;
    
-	b3HashMap<b3HashInt,BodyJointInfoCache*> m_bodyJointMap;
-	b3HashMap<b3HashInt,b3UserConstraint> m_userConstraintInfoMap;
+	btHashMap<btHashInt,BodyJointInfoCache*> m_bodyJointMap;
+	btHashMap<btHashInt,b3UserConstraint> m_userConstraintInfoMap;
 
-    b3AlignedObjectArray<TmpFloat3> m_debugLinesFrom;
-    b3AlignedObjectArray<TmpFloat3> m_debugLinesTo;
-    b3AlignedObjectArray<TmpFloat3> m_debugLinesColor;
+    btAlignedObjectArray<TmpFloat3> m_debugLinesFrom;
+    btAlignedObjectArray<TmpFloat3> m_debugLinesTo;
+    btAlignedObjectArray<TmpFloat3> m_debugLinesColor;
 
 	int m_cachedCameraPixelsWidth;
 	int m_cachedCameraPixelsHeight;
-	b3AlignedObjectArray<unsigned char> m_cachedCameraPixelsRGBA;
-	b3AlignedObjectArray<float> m_cachedCameraDepthBuffer;
-	b3AlignedObjectArray<int> m_cachedSegmentationMaskBuffer;
+	btAlignedObjectArray<unsigned char> m_cachedCameraPixelsRGBA;
+	btAlignedObjectArray<float> m_cachedCameraDepthBuffer;
+	btAlignedObjectArray<int> m_cachedSegmentationMaskBuffer;
 
-    b3AlignedObjectArray<b3ContactPointData> m_cachedContactPoints;
-	b3AlignedObjectArray<b3OverlappingObject> m_cachedOverlappingObjects;
-	b3AlignedObjectArray<b3VisualShapeData> m_cachedVisualShapes;
-	b3AlignedObjectArray<b3CollisionShapeData> m_cachedCollisionShapes;
+    btAlignedObjectArray<b3ContactPointData> m_cachedContactPoints;
+	btAlignedObjectArray<b3OverlappingObject> m_cachedOverlappingObjects;
+	btAlignedObjectArray<b3VisualShapeData> m_cachedVisualShapes;
+	btAlignedObjectArray<b3CollisionShapeData> m_cachedCollisionShapes;
 
-	b3AlignedObjectArray<b3VRControllerEvent> m_cachedVREvents;
-	b3AlignedObjectArray<b3KeyboardEvent> m_cachedKeyboardEvents;
-	b3AlignedObjectArray<b3MouseEvent> m_cachedMouseEvents;
-	b3AlignedObjectArray<double> m_cachedMassMatrix;
-	b3AlignedObjectArray<b3RayHitInfo>	m_raycastHits;
+	btAlignedObjectArray<b3VRControllerEvent> m_cachedVREvents;
+	btAlignedObjectArray<b3KeyboardEvent> m_cachedKeyboardEvents;
+	btAlignedObjectArray<b3MouseEvent> m_cachedMouseEvents;
+	btAlignedObjectArray<double> m_cachedMassMatrix;
+	btAlignedObjectArray<b3RayHitInfo>	m_raycastHits;
 
-    b3AlignedObjectArray<int> m_bodyIdsRequestInfo;
-	b3AlignedObjectArray<int> m_constraintIdsRequestInfo;
+    btAlignedObjectArray<int> m_bodyIdsRequestInfo;
+	btAlignedObjectArray<int> m_constraintIdsRequestInfo;
+
+	btAlignedObjectArray<b3UserDataGlobalIdentifier> m_userDataIdsRequestInfo;
 
     SharedMemoryStatus m_tempBackupServerStatus;
     
@@ -1285,6 +1305,33 @@ const SharedMemoryStatus* PhysicsClientSharedMemory::processServerStatus() {
 				{
 					break;
 				}
+			case CMD_SYNC_USER_DATA_FAILED:
+			{
+				b3Warning("Synchronizing user data failed.");
+				break;
+			}
+			case CMD_REQUEST_USER_DATA_FAILED:
+			{
+				b3Warning("Requesting user data failed");
+				break;
+			}
+			case CMD_ADD_USER_DATA_FAILED:
+			{
+				b3Warning("Adding user data failed (do the specified body and link exist?)");
+				break;
+			}
+			case CMD_REMOVE_USER_DATA_FAILED:
+			{
+				b3Warning("Removing user data failed");
+				break;
+			}
+			case CMD_REQUEST_USER_DATA_COMPLETED:
+			case CMD_SYNC_USER_DATA_COMPLETED:
+			case CMD_REMOVE_USER_DATA_COMPLETED:
+			case CMD_ADD_USER_DATA_COMPLETED:
+			{
+				break;
+			}
             default: {
                 b3Error("Unknown server status %d\n", serverCmd.m_type);
                 btAssert(0);
@@ -1336,6 +1383,94 @@ const SharedMemoryStatus* PhysicsClientSharedMemory::processServerStatus() {
             }
         }
 
+		if (serverCmd.m_type == CMD_SYNC_USER_DATA_COMPLETED) {
+			B3_PROFILE("CMD_SYNC_USER_DATA_COMPLETED");
+			const int numIdentifiers = serverCmd.m_syncUserDataArgs.m_numUserDataIdentifiers;
+			if (numIdentifiers > 0) {
+				m_data->m_tempBackupServerStatus = m_data->m_lastServerStatus;
+
+				const b3UserDataGlobalIdentifier *identifiers = (b3UserDataGlobalIdentifier *)m_data->m_testBlock1->m_bulletStreamDataServerToClientRefactor;
+				for (int i=0; i<numIdentifiers; i++) {
+					m_data->m_userDataIdsRequestInfo.push_back(identifiers[i]);
+				}
+
+				// Request individual user data entries.
+				const b3UserDataGlobalIdentifier userDataGlobalId = m_data->m_userDataIdsRequestInfo[m_data->m_userDataIdsRequestInfo.size()-1];
+				m_data->m_userDataIdsRequestInfo.pop_back();
+
+				SharedMemoryCommand& command = m_data->m_testBlock1->m_clientCommands[0];
+				command.m_type = CMD_REQUEST_USER_DATA;
+				command.m_userDataRequestArgs = userDataGlobalId;
+				submitClientCommand(command);
+				return 0;
+			}
+		}
+
+		if (serverCmd.m_type == CMD_ADD_USER_DATA_COMPLETED || serverCmd.m_type == CMD_REQUEST_USER_DATA_COMPLETED) {
+			B3_PROFILE("CMD_ADD_USER_DATA_COMPLETED");
+			const b3UserDataGlobalIdentifier userDataGlobalId = serverCmd.m_userDataResponseArgs.m_userDataGlobalId;
+			BodyJointInfoCache** bodyJointsPtr = m_data->m_bodyJointMap[userDataGlobalId.m_bodyUniqueId];
+			if (bodyJointsPtr && *bodyJointsPtr) {
+				UserDataCache* userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[userDataGlobalId.m_linkIndex];
+				if (!userDataCachePtr) 
+				{
+					UserDataCache cache;
+					(*bodyJointsPtr)->m_jointToUserDataMap.insert(userDataGlobalId.m_linkIndex, cache);
+				}
+				userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[userDataGlobalId.m_linkIndex];
+
+				const char *dataStream = m_data->m_testBlock1->m_bulletStreamDataServerToClientRefactor;
+				
+				SharedMemoryUserData* userDataPtr = (userDataCachePtr)->m_userDataMap[userDataGlobalId.m_userDataId];
+				if (userDataPtr) {
+					// Only replace the value.
+					userDataPtr->replaceValue(dataStream, serverCmd.m_userDataResponseArgs.m_valueLength, serverCmd.m_userDataResponseArgs.m_valueType);
+				}
+				else {
+					// Add a new user data entry.
+					const char *key = serverCmd.m_userDataResponseArgs.m_key;
+					(userDataCachePtr)->m_userDataMap.insert(userDataGlobalId.m_userDataId, SharedMemoryUserData(key));
+					(userDataCachePtr)->m_keyToUserDataIdMap.insert(key, userDataGlobalId.m_userDataId);
+					userDataPtr = (userDataCachePtr)->m_userDataMap[userDataGlobalId.m_userDataId];
+					userDataPtr->replaceValue(dataStream, serverCmd.m_userDataResponseArgs.m_valueLength, serverCmd.m_userDataResponseArgs.m_valueType);
+				}
+			}
+		}
+
+		if (serverCmd.m_type == CMD_REQUEST_USER_DATA_COMPLETED) {
+
+			if (m_data->m_userDataIdsRequestInfo.size() > 0) {
+				// Request individual user data entries.
+				const b3UserDataGlobalIdentifier userDataGlobalId = m_data->m_userDataIdsRequestInfo[m_data->m_userDataIdsRequestInfo.size()-1];
+				m_data->m_userDataIdsRequestInfo.pop_back();
+
+				SharedMemoryCommand& command = m_data->m_testBlock1->m_clientCommands[0];
+				command.m_type = CMD_REQUEST_USER_DATA;
+				command.m_userDataRequestArgs = userDataGlobalId;
+				submitClientCommand(command);
+				return 0;
+			}
+			m_data->m_lastServerStatus = m_data->m_tempBackupServerStatus;
+		}
+
+		if (serverCmd.m_type == CMD_REMOVE_USER_DATA_COMPLETED) {
+			B3_PROFILE("CMD_REMOVE_USER_DATA_COMPLETED");
+			const b3UserDataGlobalIdentifier userDataGlobalId = serverCmd.m_removeUserDataResponseArgs;
+			BodyJointInfoCache** bodyJointsPtr = m_data->m_bodyJointMap[userDataGlobalId.m_bodyUniqueId];
+			if (bodyJointsPtr && *bodyJointsPtr) {
+				UserDataCache* userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[userDataGlobalId.m_linkIndex];
+				if (userDataCachePtr) 
+				{
+					SharedMemoryUserData *userDataPtr = (userDataCachePtr)->m_userDataMap[userDataGlobalId.m_userDataId];
+					if (userDataPtr) 
+					{
+						(userDataCachePtr)->m_keyToUserDataIdMap.remove((userDataPtr)->m_key.c_str());
+						(userDataCachePtr)->m_userDataMap.remove(userDataGlobalId.m_userDataId);
+					}
+				}
+			}
+		}
+
 		if (serverCmd.m_type == CMD_REMOVE_BODY_COMPLETED)
 		{
 			for (int i=0;i<serverCmd.m_removeObjectArgs.m_numBodies;i++)
@@ -1663,3 +1798,73 @@ double PhysicsClientSharedMemory::getTimeOut() const
 {
 	return m_data->m_timeOutInSeconds;
 }
+
+bool PhysicsClientSharedMemory::getCachedUserData(int bodyUniqueId, int linkIndex, int userDataId, struct b3UserDataValue &valueOut) const {
+	BodyJointInfoCache** bodyJointsPtr = m_data->m_bodyJointMap[bodyUniqueId];
+	if (!bodyJointsPtr || !(*bodyJointsPtr)) {
+		return false;
+	}
+	UserDataCache* userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[linkIndex];
+	if (!userDataCachePtr) {
+		return false;
+	}
+	SharedMemoryUserData *userDataPtr = (userDataCachePtr)->m_userDataMap[userDataId];
+	if (!userDataPtr) 
+	{
+		return false;
+	}
+	valueOut.m_type = (userDataPtr)->m_type;
+	valueOut.m_length = userDataPtr->m_bytes.size();
+	valueOut.m_data1 = userDataPtr->m_bytes.size()? &userDataPtr->m_bytes[0] : 0;
+	return true;
+}
+
+int PhysicsClientSharedMemory::getCachedUserDataId(int bodyUniqueId, int linkIndex, const char *key) const {
+	BodyJointInfoCache** bodyJointsPtr = m_data->m_bodyJointMap[bodyUniqueId];
+	if (!bodyJointsPtr || !(*bodyJointsPtr)) {
+		return -1;
+	}
+	UserDataCache* userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[linkIndex];
+	if (!userDataCachePtr) 
+	{
+		return -1;
+	}
+	int *userDataId = (userDataCachePtr)->m_keyToUserDataIdMap[key];
+	if (!userDataId) {
+		return -1;
+	}
+	return *userDataId;
+}
+
+int PhysicsClientSharedMemory::getNumUserData(int bodyUniqueId, int linkIndex) const {
+	BodyJointInfoCache** bodyJointsPtr = m_data->m_bodyJointMap[bodyUniqueId];
+	if (!bodyJointsPtr || !(*bodyJointsPtr)) {
+		return 0;
+	}
+	UserDataCache* userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[linkIndex];
+	if (!userDataCachePtr) 
+	{
+		return 0;
+	}
+	return (userDataCachePtr)->m_userDataMap.size();
+}
+
+void PhysicsClientSharedMemory::getUserDataInfo(int bodyUniqueId, int linkIndex, int userDataIndex, const char **keyOut, int *userDataIdOut) const {
+	BodyJointInfoCache** bodyJointsPtr = m_data->m_bodyJointMap[bodyUniqueId];
+	if (!bodyJointsPtr || !(*bodyJointsPtr)) 
+	{
+		*keyOut = 0;
+		*userDataIdOut = -1;
+		return;
+	}
+	UserDataCache* userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[linkIndex];
+	if (!userDataCachePtr || userDataIndex >= (userDataCachePtr)->m_userDataMap.size()) 
+	{
+		*keyOut = 0;
+		*userDataIdOut = -1;
+		return;
+	}
+	*userDataIdOut = (userDataCachePtr)->m_userDataMap.getKeyAtIndex(userDataIndex).getUid1();
+	SharedMemoryUserData *userDataPtr = (userDataCachePtr)->m_userDataMap.getAtIndex(userDataIndex);
+	*keyOut = (userDataPtr)->m_key.c_str();
+}
diff --git a/examples/SharedMemory/PhysicsClientSharedMemory.h b/examples/SharedMemory/PhysicsClientSharedMemory.h
index ccc8c07ed..441fceb8d 100644
--- a/examples/SharedMemory/PhysicsClientSharedMemory.h
+++ b/examples/SharedMemory/PhysicsClientSharedMemory.h
@@ -83,6 +83,11 @@ public:
 	virtual void setTimeOut(double timeOutInSeconds);
 	virtual double getTimeOut() const;
 
+    virtual bool getCachedUserData(int bodyUniqueId, int linkIndex, int userDataId, struct b3UserDataValue &valueOut) const;
+    virtual int getCachedUserDataId(int bodyUniqueId, int linkIndex, const char *key) const;
+    virtual int getNumUserData(int bodyUniqueId, int linkIndex) const;
+    virtual void getUserDataInfo(int bodyUniqueId, int linkIndex, int userDataIndex, const char **keyOut, int *userDataIdOut) const;
+
 };
 
 #endif  // BT_PHYSICS_CLIENT_API_H
diff --git a/examples/SharedMemory/PhysicsDirect.cpp b/examples/SharedMemory/PhysicsDirect.cpp
index 969604f8c..6bf1004a0 100644
--- a/examples/SharedMemory/PhysicsDirect.cpp
+++ b/examples/SharedMemory/PhysicsDirect.cpp
@@ -13,11 +13,27 @@
 #include "BodyJointInfoUtility.h"
 #include <string>
 
+#include "SharedMemoryUserData.h"
+
+struct UserDataCache {
+	btHashMap<btHashInt, SharedMemoryUserData> m_userDataMap;
+	btHashMap<btHashString, int> m_keyToUserDataIdMap;
+
+	~UserDataCache() {
+	}
+};
+
 struct BodyJointInfoCache2
 {
 	std::string m_baseName;
 	btAlignedObjectArray<b3JointInfo> m_jointInfo;
 	std::string m_bodyName;
+
+	// Joint index -> user data.
+	btHashMap<btHashInt, UserDataCache> m_jointToUserDataMap;
+
+	~BodyJointInfoCache2() {
+	}
 };
 
 
@@ -651,6 +667,38 @@ void PhysicsDirect::processBodyJointInfo(int bodyUniqueId, const SharedMemorySta
     }
 }
 
+void PhysicsDirect::processAddUserData(const struct SharedMemoryStatus& serverCmd) {
+	const b3UserDataGlobalIdentifier userDataGlobalId = serverCmd.m_userDataResponseArgs.m_userDataGlobalId;
+	BodyJointInfoCache2** bodyJointsPtr = m_data->m_bodyJointMap[userDataGlobalId.m_bodyUniqueId];
+	if (bodyJointsPtr && *bodyJointsPtr) 
+	{
+		UserDataCache* userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[userDataGlobalId.m_linkIndex];
+		if (!userDataCachePtr) 
+		{
+			UserDataCache cache;
+			(*bodyJointsPtr)->m_jointToUserDataMap.insert(userDataGlobalId.m_linkIndex, cache);
+		}
+		userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[userDataGlobalId.m_linkIndex];
+
+		const char *dataStream = m_data->m_bulletStreamDataServerToClient;
+
+		b3UserDataValue userDataValue;
+		userDataValue.m_type = serverCmd.m_userDataResponseArgs.m_valueType;
+		userDataValue.m_length = serverCmd.m_userDataResponseArgs.m_valueLength;
+		SharedMemoryUserData *userDataPtr = userDataCachePtr->m_userDataMap[userDataGlobalId.m_userDataId];
+		if (userDataPtr) {
+			// Only replace the value.
+			(userDataPtr)->replaceValue(dataStream,serverCmd.m_userDataResponseArgs.m_valueLength,userDataValue.m_type);
+		}
+		else {
+			// Add a new user data entry.
+			(userDataCachePtr)->m_userDataMap.insert(userDataGlobalId.m_userDataId, SharedMemoryUserData(serverCmd.m_userDataResponseArgs.m_key));
+			userDataPtr = (userDataCachePtr)->m_userDataMap[userDataGlobalId.m_userDataId];
+			userDataPtr->replaceValue(dataStream,serverCmd.m_userDataResponseArgs.m_valueLength,userDataValue.m_type);
+		}
+	}
+}
+
 void PhysicsDirect::postProcessStatus(const struct SharedMemoryStatus& serverCmd)
 {
 	switch (serverCmd.m_type)
@@ -1056,6 +1104,73 @@ void PhysicsDirect::postProcessStatus(const struct SharedMemoryStatus& serverCmd
 	{
 		break;
 	}
+	case CMD_SYNC_USER_DATA_FAILED:
+	{
+		b3Warning("Synchronizing user data failed.");
+		break;
+	}
+	case CMD_ADD_USER_DATA_FAILED:
+	{
+		b3Warning("Adding user data failed (do the specified body and link exist?)");
+		break;
+	}
+	case CMD_REMOVE_USER_DATA_FAILED:
+	{
+		b3Warning("Removing user data failed");
+		break;
+	}
+	case CMD_ADD_USER_DATA_COMPLETED:
+	{
+		processAddUserData(serverCmd);
+		break;
+	}
+	case CMD_SYNC_USER_DATA_COMPLETED:
+	{
+		B3_PROFILE("CMD_SYNC_USER_DATA_COMPLETED");
+		const int numIdentifiers = serverCmd.m_syncUserDataArgs.m_numUserDataIdentifiers;
+		b3UserDataGlobalIdentifier *identifiers = new b3UserDataGlobalIdentifier[numIdentifiers];
+		memcpy(identifiers, &m_data->m_bulletStreamDataServerToClient[0], numIdentifiers * sizeof(b3UserDataGlobalIdentifier));
+
+		for (int i=0; i<numIdentifiers; i++) {
+			m_data->m_tmpInfoRequestCommand.m_type = CMD_REQUEST_USER_DATA;
+			m_data->m_tmpInfoRequestCommand.m_userDataRequestArgs = identifiers[i];
+
+			bool hasStatus = m_data->m_commandProcessor->processCommand(m_data->m_tmpInfoRequestCommand, m_data->m_tmpInfoStatus, &m_data->m_bulletStreamDataServerToClient[0], SHARED_MEMORY_MAX_STREAM_CHUNK_SIZE);
+
+			b3Clock clock;
+			double startTime = clock.getTimeInSeconds();
+			double timeOutInSeconds = m_data->m_timeOutInSeconds;
+
+			while ((!hasStatus) && (clock.getTimeInSeconds()-startTime < timeOutInSeconds))
+			{
+				hasStatus = m_data->m_commandProcessor->receiveStatus(m_data->m_tmpInfoStatus, &m_data->m_bulletStreamDataServerToClient[0], SHARED_MEMORY_MAX_STREAM_CHUNK_SIZE);
+			}
+
+			if (hasStatus)
+			{
+				processAddUserData(m_data->m_tmpInfoStatus);
+			}
+		}
+		delete[] identifiers;
+		break;
+	}
+	case CMD_REMOVE_USER_DATA_COMPLETED:
+	{
+		const b3UserDataGlobalIdentifier userDataGlobalId = serverCmd.m_removeUserDataResponseArgs;
+		BodyJointInfoCache2** bodyJointsPtr = m_data->m_bodyJointMap[userDataGlobalId.m_bodyUniqueId];
+		if (bodyJointsPtr && *bodyJointsPtr) {
+			UserDataCache *userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[userDataGlobalId.m_linkIndex];
+			if (userDataCachePtr) 
+			{
+				SharedMemoryUserData* userDataPtr = (userDataCachePtr)->m_userDataMap[userDataGlobalId.m_userDataId];
+				if (userDataPtr) {
+					(userDataCachePtr)->m_keyToUserDataIdMap.remove((userDataPtr)->m_key.c_str());
+					(userDataCachePtr)->m_userDataMap.remove(userDataGlobalId.m_userDataId);
+				}
+			}
+		}
+		break;
+	}
 	default:
 	{
 		//b3Warning("Unknown server status type");
@@ -1331,3 +1446,71 @@ double PhysicsDirect::getTimeOut() const
 {
 	return m_data->m_timeOutInSeconds;
 }
+
+bool PhysicsDirect::getCachedUserData(int bodyUniqueId, int linkIndex, int userDataId, struct b3UserDataValue &valueOut) const {
+	BodyJointInfoCache2** bodyJointsPtr = m_data->m_bodyJointMap[bodyUniqueId];
+	if (!bodyJointsPtr || !(*bodyJointsPtr)) {
+		return false;
+	}
+	UserDataCache* userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[linkIndex];
+	if (!userDataCachePtr) 
+	{
+		return false;
+	}
+	SharedMemoryUserData* userDataPtr = (userDataCachePtr)->m_userDataMap[userDataId];
+	if (!userDataPtr) 
+	{
+		return false;
+	}
+	valueOut.m_type = userDataPtr->m_type;
+	valueOut.m_length = userDataPtr->m_bytes.size();
+	valueOut.m_data1 = userDataPtr->m_bytes.size()? &userDataPtr->m_bytes[0] : 0;
+	return true;
+}
+
+int PhysicsDirect::getCachedUserDataId(int bodyUniqueId, int linkIndex, const char *key) const {
+	BodyJointInfoCache2** bodyJointsPtr = m_data->m_bodyJointMap[bodyUniqueId];
+	if (!bodyJointsPtr || !(*bodyJointsPtr)) {
+		return -1;
+	}
+	UserDataCache* userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[linkIndex];
+	if (!userDataCachePtr) {
+		return -1;
+	}
+	int *userDataId = (userDataCachePtr)->m_keyToUserDataIdMap[key];
+	if (!userDataId) {
+		return -1;
+	}
+	return *userDataId;
+}
+
+int PhysicsDirect::getNumUserData(int bodyUniqueId, int linkIndex) const {
+	BodyJointInfoCache2** bodyJointsPtr = m_data->m_bodyJointMap[bodyUniqueId];
+	if (!bodyJointsPtr || !(*bodyJointsPtr)) {
+		return 0;
+	}
+	UserDataCache* userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[linkIndex];
+	if (!userDataCachePtr) {
+		return 0;
+	}
+	return (userDataCachePtr)->m_userDataMap.size();
+}
+
+void PhysicsDirect::getUserDataInfo(int bodyUniqueId, int linkIndex, int userDataIndex, const char **keyOut, int *userDataIdOut) const {
+	BodyJointInfoCache2** bodyJointsPtr = m_data->m_bodyJointMap[bodyUniqueId];
+	if (!bodyJointsPtr || !(*bodyJointsPtr)) {
+		*keyOut = 0;
+		*userDataIdOut = -1;
+		return;
+	}
+	UserDataCache* userDataCachePtr = (*bodyJointsPtr)->m_jointToUserDataMap[linkIndex];
+	if (!userDataCachePtr || userDataIndex >= (userDataCachePtr)->m_userDataMap.size()) 
+	{
+		*keyOut = 0;
+		*userDataIdOut = -1;
+		return;
+	}
+	*userDataIdOut = (userDataCachePtr)->m_userDataMap.getKeyAtIndex(userDataIndex).getUid1();
+	SharedMemoryUserData* userDataPtr = (userDataCachePtr)->m_userDataMap.getAtIndex(userDataIndex);
+	*keyOut = (userDataPtr)->m_key.c_str();
+}
diff --git a/examples/SharedMemory/PhysicsDirect.h b/examples/SharedMemory/PhysicsDirect.h
index f2699a6f5..b02c10da8 100644
--- a/examples/SharedMemory/PhysicsDirect.h
+++ b/examples/SharedMemory/PhysicsDirect.h
@@ -25,7 +25,9 @@ protected:
 	bool processVisualShapeData(const struct SharedMemoryCommand& orgCommand);
 	
     void processBodyJointInfo(int bodyUniqueId, const struct SharedMemoryStatus& serverCmd);
-    
+
+	void processAddUserData(const struct SharedMemoryStatus& serverCmd);
+
 	void postProcessStatus(const struct SharedMemoryStatus& serverCmd);
 
 	void resetData();
@@ -110,6 +112,11 @@ public:
 
 	virtual void setTimeOut(double timeOutInSeconds);
 	virtual double getTimeOut() const;
+
+    virtual bool getCachedUserData(int bodyUniqueId, int linkIndex, int userDataId, struct b3UserDataValue &valueOut) const;
+    virtual int getCachedUserDataId(int bodyUniqueId, int linkIndex, const char *key) const;
+    virtual int getNumUserData(int bodyUniqueId, int linkIndex) const;
+    virtual void getUserDataInfo(int bodyUniqueId, int linkIndex, int userDataIndex, const char **keyOut, int *userDataIdOut) const;
 };
 
 #endif //PHYSICS_DIRECT_H
diff --git a/examples/SharedMemory/PhysicsLoopBack.cpp b/examples/SharedMemory/PhysicsLoopBack.cpp
index 0606588e6..b7a2dd13c 100644
--- a/examples/SharedMemory/PhysicsLoopBack.cpp
+++ b/examples/SharedMemory/PhysicsLoopBack.cpp
@@ -225,3 +225,19 @@ double PhysicsLoopBack::getTimeOut() const
 	return m_data->m_physicsClient->getTimeOut();
 }
 
+bool PhysicsLoopBack::getCachedUserData(int bodyUniqueId, int linkIndex, int userDataId, struct b3UserDataValue &valueOut) const {
+	return m_data->m_physicsClient->getCachedUserData(bodyUniqueId, linkIndex, userDataId, valueOut);
+}
+
+int PhysicsLoopBack::getCachedUserDataId(int bodyUniqueId, int linkIndex, const char *key) const {
+	return m_data->m_physicsClient->getCachedUserDataId(bodyUniqueId, linkIndex, key);
+}
+
+int PhysicsLoopBack::getNumUserData(int bodyUniqueId, int linkIndex) const {
+	return m_data->m_physicsClient->getNumUserData(bodyUniqueId, linkIndex);
+}
+
+void PhysicsLoopBack::getUserDataInfo(int bodyUniqueId, int linkIndex, int userDataIndex, const char **keyOut, int *userDataIdOut) const {
+	m_data->m_physicsClient->getUserDataInfo(bodyUniqueId, linkIndex, userDataIndex, keyOut, userDataIdOut);
+}
+
diff --git a/examples/SharedMemory/PhysicsLoopBack.h b/examples/SharedMemory/PhysicsLoopBack.h
index f4591ed99..afa42817b 100644
--- a/examples/SharedMemory/PhysicsLoopBack.h
+++ b/examples/SharedMemory/PhysicsLoopBack.h
@@ -86,6 +86,11 @@ public:
 
 	virtual void setTimeOut(double timeOutInSeconds);
 	virtual double getTimeOut() const;
+
+    virtual bool getCachedUserData(int bodyUniqueId, int linkIndex, int userDataId, struct b3UserDataValue &valueOut) const;
+    virtual int getCachedUserDataId(int bodyUniqueId, int linkIndex, const char *key) const;
+    virtual int getNumUserData(int bodyUniqueId, int linkIndex) const;
+    virtual void getUserDataInfo(int bodyUniqueId, int linkIndex, int userDataIndex, const char **keyOut, int *userDataIdOut) const;
 };
 
 #endif //PHYSICS_LOOP_BACK_H
diff --git a/examples/SharedMemory/PhysicsServerCommandProcessor.cpp b/examples/SharedMemory/PhysicsServerCommandProcessor.cpp
index a3cb2bdf6..0e1501b8a 100644
--- a/examples/SharedMemory/PhysicsServerCommandProcessor.cpp
+++ b/examples/SharedMemory/PhysicsServerCommandProcessor.cpp
@@ -176,6 +176,74 @@ struct InternalCollisionShapeData
 	}
 };
 
+#include "SharedMemoryUserData.h"
+
+/**
+ * Holds all custom user data entries for a link.
+ */
+struct InternalLinkUserData {
+	// Used to look up user data entry handles for string keys.
+	btHashMap<btHashString, int> m_keyToHandleMap;
+	b3ResizablePool<b3PoolBodyHandle<SharedMemoryUserData> > m_userData;
+
+	// Adds or replaces a user data entry. 
+	// Returns the user data handle.
+	const int add(const char* key, const char* bytes, int len, int type) 
+	{
+		// If an entry with the key already exists, just update the value.
+		int userDataId = getUserDataId(key);
+		if (userDataId != -1) {
+			SharedMemoryUserData* userData = m_userData.getHandle(userDataId);
+			b3Assert(userData);
+			userData->replaceValue(bytes, len, type);
+			return userDataId;
+		}
+
+		userDataId = m_userData.allocHandle();
+		SharedMemoryUserData* userData = m_userData.getHandle(userDataId);
+		userData->m_key = key;
+		userData->replaceValue(bytes, len, type);
+		m_keyToHandleMap.insert(userData->m_key.c_str(), userDataId);
+		return userDataId;
+	}
+
+	// Returns the user data handle for a specified key or -1 if not found.
+	const int getUserDataId(const char* key) const 
+	{
+		const int* userDataIdPtr = m_keyToHandleMap.find(key);
+		if (userDataIdPtr) 
+		{
+			return *userDataIdPtr;
+		}
+		return -1;
+	}
+
+	// Removes a user data entry given the handle.
+	// Returns true when the entry was removed, false otherwise.
+	const bool remove(int userDataId) 
+	{
+		const SharedMemoryUserData* userData = m_userData.getHandle(userDataId);
+		if (!userData) 
+		{
+			return false;
+		}
+		m_keyToHandleMap.remove(userData->m_key.c_str());
+		m_userData.freeHandle(userDataId);
+		return true;
+	}
+
+	// Returns the user data given the user data id. null otherwise.
+	const SharedMemoryUserData* getUserData(const int userDataId) const 
+	{
+	    return m_userData.getHandle(userDataId);
+	}
+
+	void getUserDataIds(b3AlignedObjectArray<int> &userDataIds) const 
+	{
+		m_userData.getUsedHandles(userDataIds);
+	}
+};
+
 struct InternalBodyData
 {
 	btMultiBody* m_multiBody;
@@ -191,7 +259,7 @@ struct InternalBodyData
 	btAlignedObjectArray<btGeneric6DofSpring2Constraint*> m_rigidBodyJoints;
 	btAlignedObjectArray<std::string> m_rigidBodyJointNames;
 	btAlignedObjectArray<std::string> m_rigidBodyLinkNames;
-	
+	btHashMap<btHashInt, InternalLinkUserData*> m_linkUserDataMap;
 	
 #ifdef B3_ENABLE_TINY_AUDIO
 	b3HashMap<btHashInt, SDFAudioSource> m_audioSources;
@@ -216,6 +284,10 @@ struct InternalBodyData
 		m_rigidBodyJoints.clear();
 		m_rigidBodyJointNames.clear();
 		m_rigidBodyLinkNames.clear();
+		for(int i=0; i<m_linkUserDataMap.size(); i++) {
+			delete *m_linkUserDataMap.getAtIndex(i);
+		}
+		m_linkUserDataMap.clear();
 	}
 
 };
@@ -1484,7 +1556,6 @@ struct SaveStateData
 	btSerializer* m_serializer;
 };
 
-
 struct PhysicsServerCommandProcessorInternalData
 {
 	///handle management
@@ -4726,6 +4797,139 @@ bool PhysicsServerCommandProcessor::processSyncBodyInfoCommand(const struct Shar
 	return hasStatus;
 }
 
+bool PhysicsServerCommandProcessor::processSyncUserDataCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes)
+{
+	bool hasStatus = true;
+	BT_PROFILE("CMD_SYNC_USER_DATA");
+
+	b3UserDataGlobalIdentifier *userDataIdentifiers = (b3UserDataGlobalIdentifier *)bufferServerToClient;
+	int numIdentifiers = 0;
+	b3AlignedObjectArray<int> bodyHandles;
+	m_data->m_bodyHandles.getUsedHandles(bodyHandles);
+	for (int i=0; i<bodyHandles.size(); i++) {
+		int bodyHandle = bodyHandles[i];
+		InternalBodyData* body = m_data->m_bodyHandles.getHandle(bodyHandle);
+		if (!body) {
+			continue;
+		}
+		for (int j=0; j<body->m_linkUserDataMap.size(); j++) {
+			const int linkIndex = body->m_linkUserDataMap.getKeyAtIndex(j).getUid1();
+			InternalLinkUserData **userDataPtr = body->m_linkUserDataMap.getAtIndex(j);
+			if (!userDataPtr) {
+				continue;
+			}
+			b3AlignedObjectArray<int> userDataIds;
+			(*userDataPtr)->getUserDataIds(userDataIds);
+			for (int k=0; k<userDataIds.size(); k++) {
+				b3UserDataGlobalIdentifier &identifier = userDataIdentifiers[numIdentifiers++];
+				identifier.m_bodyUniqueId = bodyHandle;
+				identifier.m_linkIndex = linkIndex;
+				identifier.m_userDataId = userDataIds[k];
+			}
+		}
+	}
+
+	serverStatusOut.m_syncUserDataArgs.m_numUserDataIdentifiers = numIdentifiers;
+	serverStatusOut.m_type = CMD_SYNC_USER_DATA_COMPLETED;
+	return hasStatus;
+}
+
+bool PhysicsServerCommandProcessor::processRequestUserDataCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes)
+{
+	bool hasStatus = true;
+	BT_PROFILE("CMD_REQUEST_USER_DATA");
+	serverStatusOut.m_type = CMD_REQUEST_USER_DATA_FAILED;
+
+	InternalBodyData *body = m_data->m_bodyHandles.getHandle(clientCmd.m_userDataRequestArgs.m_bodyUniqueId);
+	if (!body) {
+		return hasStatus;
+	}
+	const int linkIndex = clientCmd.m_userDataRequestArgs.m_linkIndex;
+	InternalLinkUserData **userDataPtr = body->m_linkUserDataMap[linkIndex];
+	if (!userDataPtr) {
+		return hasStatus;
+	}
+	const SharedMemoryUserData *userData = (*userDataPtr)->getUserData(clientCmd.m_userDataRequestArgs.m_userDataId);
+	if (!userData) {
+		return hasStatus;
+	}
+	btAssert(bufferSizeInBytes >= userData->m_bytes.size())
+	serverStatusOut.m_userDataResponseArgs.m_userDataGlobalId = clientCmd.m_userDataRequestArgs;
+	serverStatusOut.m_userDataResponseArgs.m_valueType = userData->m_type;
+	serverStatusOut.m_userDataResponseArgs.m_valueLength = userData->m_bytes.size();
+	serverStatusOut.m_type = CMD_REQUEST_USER_DATA_COMPLETED;
+
+	strcpy(serverStatusOut.m_userDataResponseArgs.m_key, userData->m_key.c_str());
+	if (userData->m_bytes.size())
+	{
+		memcpy(bufferServerToClient, &userData->m_bytes[0], userData->m_bytes.size());
+	}
+	return hasStatus;
+}
+
+bool PhysicsServerCommandProcessor::processAddUserDataCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes)
+{
+	bool hasStatus = true;
+	BT_PROFILE("CMD_ADD_USER_DATA");
+	serverStatusOut.m_type = CMD_ADD_USER_DATA_FAILED;
+
+	if (clientCmd.m_addUserDataRequestArgs.m_bodyUniqueId< 0 || clientCmd.m_addUserDataRequestArgs.m_bodyUniqueId >= m_data->m_bodyHandles.getNumHandles())
+	{
+		return hasStatus;
+	}
+	
+	InternalBodyData *body = m_data->m_bodyHandles.getHandle(clientCmd.m_addUserDataRequestArgs.m_bodyUniqueId);
+	if (!body) {
+		return hasStatus;
+	}
+	const int linkIndex = clientCmd.m_addUserDataRequestArgs.m_linkIndex;
+	InternalLinkUserData **userDataPtr = body->m_linkUserDataMap[linkIndex];
+	if (!userDataPtr) {
+		InternalLinkUserData *userData = new InternalLinkUserData;
+		userDataPtr = &userData;
+		body->m_linkUserDataMap.insert(linkIndex, userData);
+	}
+
+	const int userDataId = (*userDataPtr)->add(clientCmd.m_addUserDataRequestArgs.m_key,
+		 bufferServerToClient,clientCmd.m_addUserDataRequestArgs.m_valueLength,
+		clientCmd.m_addUserDataRequestArgs.m_valueType);
+
+	serverStatusOut.m_type = CMD_ADD_USER_DATA_COMPLETED;
+	serverStatusOut.m_userDataResponseArgs.m_userDataGlobalId.m_userDataId = userDataId;
+	serverStatusOut.m_userDataResponseArgs.m_userDataGlobalId.m_bodyUniqueId = clientCmd.m_addUserDataRequestArgs.m_bodyUniqueId;
+	serverStatusOut.m_userDataResponseArgs.m_userDataGlobalId.m_linkIndex = clientCmd.m_addUserDataRequestArgs.m_linkIndex;
+	serverStatusOut.m_userDataResponseArgs.m_valueLength = clientCmd.m_addUserDataRequestArgs.m_valueLength;
+	serverStatusOut.m_userDataResponseArgs.m_valueType = clientCmd.m_addUserDataRequestArgs.m_valueType;
+	strcpy(serverStatusOut.m_userDataResponseArgs.m_key, clientCmd.m_addUserDataRequestArgs.m_key);
+
+	// Keep bufferServerToClient as-is.
+	return hasStatus;
+}
+
+bool PhysicsServerCommandProcessor::processRemoveUserDataCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes)
+{
+	bool hasStatus = true;
+	BT_PROFILE("CMD_REMOVE_USER_DATA");
+	serverStatusOut.m_type = CMD_REMOVE_USER_DATA_FAILED;
+
+	InternalBodyData *body = m_data->m_bodyHandles.getHandle(clientCmd.m_removeUserDataRequestArgs.m_bodyUniqueId);
+	if (!body) {
+		return hasStatus;
+	}
+	const int linkIndex = clientCmd.m_removeUserDataRequestArgs.m_linkIndex;
+	InternalLinkUserData **userDataPtr = body->m_linkUserDataMap[linkIndex];
+	if (!userDataPtr) {
+		return hasStatus;
+	}
+	const bool removed = (*userDataPtr)->remove(clientCmd.m_removeUserDataRequestArgs.m_userDataId);
+	if (!removed) {
+		return hasStatus;
+	}
+	serverStatusOut.m_removeUserDataResponseArgs = clientCmd.m_removeUserDataRequestArgs;
+	serverStatusOut.m_type = CMD_REMOVE_USER_DATA_COMPLETED;
+	return hasStatus;
+}
+
 bool PhysicsServerCommandProcessor::processSendDesiredStateCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes)
 {
 	bool hasStatus = true;
@@ -5804,6 +6008,12 @@ bool PhysicsServerCommandProcessor::processCreateMultiBodyCommand(const struct S
 		}						
 					
 		int flags = 0;
+
+		if (clientCmd.m_updateFlags & MULT_BODY_HAS_FLAGS)
+		{
+			flags = clientCmd.m_createMultiBodyArgs.m_flags;
+		}
+
 		bool ok = processImportedObjects("memory", bufferServerToClient, bufferSizeInBytes, useMultiBody,  flags, u2b);
 
 		if (ok)
@@ -9461,6 +9671,26 @@ bool PhysicsServerCommandProcessor::processCommand(const struct SharedMemoryComm
 			hasStatus = processCustomCommand(clientCmd,serverStatusOut,bufferServerToClient, bufferSizeInBytes);
 			break;
 		}
+	case CMD_SYNC_USER_DATA:
+		{
+			hasStatus = processSyncUserDataCommand(clientCmd,serverStatusOut,bufferServerToClient, bufferSizeInBytes);
+			break;
+		}
+	case CMD_REQUEST_USER_DATA:
+		{
+			hasStatus = processRequestUserDataCommand(clientCmd,serverStatusOut,bufferServerToClient, bufferSizeInBytes);
+			break;
+		}
+	case CMD_ADD_USER_DATA:
+		{
+			hasStatus = processAddUserDataCommand(clientCmd,serverStatusOut,bufferServerToClient, bufferSizeInBytes);
+			break;
+		}
+	case CMD_REMOVE_USER_DATA:
+		{
+			hasStatus = processRemoveUserDataCommand(clientCmd,serverStatusOut,bufferServerToClient, bufferSizeInBytes);
+			break;
+		}
 	default:
 		{
 			BT_PROFILE("CMD_UNKNOWN");
diff --git a/examples/SharedMemory/PhysicsServerCommandProcessor.h b/examples/SharedMemory/PhysicsServerCommandProcessor.h
index 24f9f2401..903f2e4e1 100644
--- a/examples/SharedMemory/PhysicsServerCommandProcessor.h
+++ b/examples/SharedMemory/PhysicsServerCommandProcessor.h
@@ -83,6 +83,10 @@ protected:
 	bool processLoadMJCFCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes);
 	bool processRestoreStateCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes);
 	bool processSaveStateCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes);
+	bool processSyncUserDataCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes);
+	bool processRequestUserDataCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes);
+	bool processAddUserDataCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes);
+	bool processRemoveUserDataCommand(const struct SharedMemoryCommand& clientCmd, struct SharedMemoryStatus& serverStatusOut, char* bufferServerToClient, int bufferSizeInBytes);
 
 	int extractCollisionShapes(const class btCollisionShape* colShape, const class btTransform& transform, struct b3CollisionShapeData* collisionShapeBuffer, int maxCollisionShapes);
 
diff --git a/examples/SharedMemory/SharedMemoryCommands.h b/examples/SharedMemory/SharedMemoryCommands.h
index d35d425cc..dd2434124 100644
--- a/examples/SharedMemory/SharedMemoryCommands.h
+++ b/examples/SharedMemory/SharedMemoryCommands.h
@@ -36,6 +36,7 @@
 #define MAX_SDF_FILENAME_LENGTH 1024
 #define MAX_FILENAME_LENGTH MAX_URDF_FILENAME_LENGTH
 #define MAX_NUM_LINKS MAX_DEGREE_OF_FREEDOM
+#define MAX_USER_DATA_KEY_LENGTH MAX_URDF_FILENAME_LENGTH
 
 struct TmpFloat3 
 {
@@ -926,6 +927,7 @@ enum eCreateMultiBodyEnum
 {
 	MULTI_BODY_HAS_BASE=1,
 	MULT_BODY_USE_MAXIMAL_COORDINATES=2,
+	MULT_BODY_HAS_FLAGS=4,
 };
 struct b3CreateMultiBodyArgs
 {
@@ -947,7 +949,7 @@ struct b3CreateMultiBodyArgs
 	int m_linkParentIndices[MAX_CREATE_MULTI_BODY_LINKS];
 	int m_linkJointTypes[MAX_CREATE_MULTI_BODY_LINKS];
 	double m_linkJointAxis[3*MAX_CREATE_MULTI_BODY_LINKS];
-
+	int m_flags;
 	#if 0
 	std::string m_name;
 	std::string m_sourceFile;
@@ -976,6 +978,32 @@ struct b3StateSerializationArguments
 	int m_stateId;
 };
 
+struct SyncUserDataArgs
+{
+	// User data identifiers stored in m_bulletStreamDataServerToClientRefactor
+	// as as array of b3UserDataGlobalIdentifier objects
+	int m_numUserDataIdentifiers;
+};
+
+struct UserDataResponseArgs
+{
+	b3UserDataGlobalIdentifier m_userDataGlobalId;
+	int m_valueType;
+	int m_valueLength;
+	char m_key[MAX_USER_DATA_KEY_LENGTH];
+	// Value data stored in m_bulletStreamDataServerToClientRefactor.
+};
+
+struct AddUserDataRequestArgs
+{
+	int m_bodyUniqueId;
+	int m_linkIndex;
+	int m_valueType;
+	int m_valueLength;
+	char m_key[MAX_USER_DATA_KEY_LENGTH];
+	// Value data stored in m_bulletStreamDataServerToClientRefactor.
+};
+
 struct SharedMemoryCommand
 {
 	int m_type;
@@ -1032,6 +1060,9 @@ struct SharedMemoryCommand
 		struct b3CustomCommand m_customCommandArgs;
 		struct b3StateSerializationArguments m_loadStateArguments;
 		struct RequestCollisionShapeDataArgs m_requestCollisionShapeDataArguments;		
+		struct b3UserDataGlobalIdentifier m_userDataRequestArgs;
+		struct AddUserDataRequestArgs m_addUserDataRequestArgs;
+		struct b3UserDataGlobalIdentifier m_removeUserDataRequestArgs;
     };
 };
 
@@ -1054,11 +1085,6 @@ struct SendOverlappingObjectsArgs
 	int m_numRemainingOverlappingObjects;
 };
 
-
-
-
-
-
 struct SharedMemoryStatus
 {
 	int m_type;
@@ -1109,6 +1135,9 @@ struct SharedMemoryStatus
 		struct b3StateSerializationArguments m_saveStateResultArgs;
 		struct b3LoadSoftBodyResultArgs m_loadSoftBodyResultArguments;
 		struct SendCollisionShapeDataArgs m_sendCollisionShapeArgs;
+		struct SyncUserDataArgs m_syncUserDataArgs;
+		struct UserDataResponseArgs m_userDataResponseArgs;
+		struct b3UserDataGlobalIdentifier m_removeUserDataResponseArgs;
 	};
 };
 
diff --git a/examples/SharedMemory/SharedMemoryPublic.h b/examples/SharedMemory/SharedMemoryPublic.h
index bfabbfb0c..4648314c7 100644
--- a/examples/SharedMemory/SharedMemoryPublic.h
+++ b/examples/SharedMemory/SharedMemoryPublic.h
@@ -5,7 +5,8 @@
 ///increase the SHARED_MEMORY_MAGIC_NUMBER whenever incompatible changes are made in the structures
 ///my convention is year/month/day/rev
 
-#define SHARED_MEMORY_MAGIC_NUMBER 201801170
+#define SHARED_MEMORY_MAGIC_NUMBER 201806020
+//#define SHARED_MEMORY_MAGIC_NUMBER 201801170
 //#define SHARED_MEMORY_MAGIC_NUMBER 201801080
 //#define SHARED_MEMORY_MAGIC_NUMBER 201801010
 //#define SHARED_MEMORY_MAGIC_NUMBER 201710180
@@ -83,9 +84,14 @@ enum EnumSharedMemoryClientCommand
 	CMD_SAVE_STATE,
 	CMD_RESTORE_STATE,
 	CMD_REQUEST_COLLISION_SHAPE_INFO,
+
+	CMD_SYNC_USER_DATA,
+	CMD_REQUEST_USER_DATA,
+	CMD_ADD_USER_DATA,
+	CMD_REMOVE_USER_DATA,
+
     //don't go beyond this command!
     CMD_MAX_CLIENT_COMMANDS,
-    
 };
 
 enum EnumSharedMemoryServerStatus
@@ -192,6 +198,15 @@ enum EnumSharedMemoryServerStatus
 		CMD_COLLISION_SHAPE_INFO_FAILED,
 		CMD_LOAD_SOFT_BODY_FAILED,
 		CMD_LOAD_SOFT_BODY_COMPLETED,
+
+		CMD_SYNC_USER_DATA_COMPLETED,
+		CMD_SYNC_USER_DATA_FAILED,
+		CMD_REQUEST_USER_DATA_COMPLETED,
+		CMD_REQUEST_USER_DATA_FAILED,
+		CMD_ADD_USER_DATA_COMPLETED,
+		CMD_ADD_USER_DATA_FAILED,
+		CMD_REMOVE_USER_DATA_COMPLETED,
+		CMD_REMOVE_USER_DATA_FAILED,
 		//don't go beyond 'CMD_MAX_SERVER_COMMANDS!
         CMD_MAX_SERVER_COMMANDS
 };
@@ -254,6 +269,27 @@ struct b3JointInfo
 };
 
 
+enum UserDataValueType {
+	// Data represents generic byte array.
+	USER_DATA_VALUE_TYPE_BYTES = 0,
+	// Data represents C-string
+	USER_DATA_VALUE_TYPE_STRING = 1,
+};
+
+struct b3UserDataValue 
+{
+	int m_type;
+	int m_length;
+	char* m_data1;
+};
+
+struct b3UserDataGlobalIdentifier 
+{
+	int m_bodyUniqueId;
+	int m_linkIndex;
+	int m_userDataId;
+};
+
 struct b3UserConstraint
 {
     int m_parentBodyIndex;
diff --git a/examples/SharedMemory/SharedMemoryUserData.h b/examples/SharedMemory/SharedMemoryUserData.h
new file mode 100644
index 000000000..a29f59eb0
--- /dev/null
+++ b/examples/SharedMemory/SharedMemoryUserData.h
@@ -0,0 +1,48 @@
+#ifndef SHARED_MEMORY_USER_DATA_H
+#define SHARED_MEMORY_USER_DATA_H
+
+#include <string>
+#include "LinearMath/btAlignedObjectArray.h"
+#include "SharedMemoryPublic.h"
+
+struct SharedMemoryUserData 
+{
+	std::string m_key;
+	int m_type;
+
+	btAlignedObjectArray<char> m_bytes;
+	
+	SharedMemoryUserData()
+		:m_type(-1)
+	{
+	}
+
+	// Takes ownership of the passed key and value arguments.
+	SharedMemoryUserData(const char* key)
+	:m_key(key)
+	{
+	}
+
+	// Takes ownership of the data pointed to by newValue.
+	void replaceValue(const char* bytes, int len, int type)
+	{
+		m_type = type;
+		m_bytes.resize(len);
+		for (int i=0;i<len;i++)
+		{
+			m_bytes[i] = bytes[i];
+		}
+	}
+
+	virtual ~SharedMemoryUserData()
+	{
+	}
+
+	void clear()
+	{
+		m_bytes.clear();
+		m_type = -1;
+	}
+};
+
+#endif //SHARED_MEMORY_USER_DATA_H
diff --git a/examples/pybullet/examples/userData.py b/examples/pybullet/examples/userData.py
new file mode 100644
index 000000000..17080a4e5
--- /dev/null
+++ b/examples/pybullet/examples/userData.py
@@ -0,0 +1,110 @@
+import pybullet as pb
+import time
+from pybullet_utils import bullet_client
+
+
+server = bullet_client.BulletClient(connection_mode=pb.GUI_SERVER)
+
+
+print ("Connecting to bullet server")
+CONNECTION_METHOD = pb.SHARED_MEMORY
+client = bullet_client.BulletClient(connection_mode=CONNECTION_METHOD)
+
+
+PLANE_PATH = "plane.urdf"
+client.loadURDF(PLANE_PATH)
+
+client.setGravity(0, 0, -10)
+
+print ("Adding plane object")
+plane_id = client.loadURDF(PLANE_PATH)
+print ("Plane ID: %s" % plane_id)
+
+print ("Adding user data to plane")
+MyKey1 = client.addUserData(plane_id, 0, "MyKey1", "MyValue1")
+MyKey2 = client.addUserData(plane_id, 0, "MyKey2", "MyValue2")
+MyKey3 = client.addUserData(plane_id, 0, "MyKey3", "MyValue3")
+MyKey4 = client.addUserData(plane_id, 0, "MyKey4", "MyValue4")
+
+print ("Retrieving cached user data")
+print (client.getUserData(plane_id, 0, MyKey1))
+print (client.getUserData(plane_id, 0, MyKey2))
+print (client.getUserData(plane_id, 0, MyKey3))
+print (client.getUserData(plane_id, 0, MyKey4))
+
+print ("Disconnecting")
+del client
+
+print ("Reconnecting")
+client = bullet_client.BulletClient(connection_mode=CONNECTION_METHOD)
+
+print ("Retrieving synced user data")
+print (client.getUserData(plane_id, 0, MyKey1))
+print (client.getUserData(plane_id, 0, MyKey2))
+print (client.getUserData(plane_id, 0, MyKey3))
+print (client.getUserData(plane_id, 0, MyKey4))
+
+print ("Number of user data entries: %s" % client.getNumUserData(plane_id, 0))
+
+print ("Overriding user data")
+client.addUserData(plane_id, 0, "MyKey1", "MyNewValue")
+
+print ("Cached overridden data")
+print (client.getUserData(plane_id, 0, MyKey1))
+
+
+print ("Disconnecting")
+del client
+
+print ("Reconnecting")
+client = bullet_client.BulletClient(connection_mode=CONNECTION_METHOD)
+
+
+print ("Synced overridden data")
+print (client.getUserData(plane_id, 0, MyKey1))
+
+print ("Getting user data ID")
+print ("Retrieved ID: %s, ID retrieved from addUserData: %s"  % (client.getUserDataId(plane_id, 0, "MyKey2"), MyKey2))
+
+print ("Removing user data")
+client.removeUserData(plane_id, 0, MyKey2)
+
+print ("Retrieving cached removed data")
+print (client.getUserData(plane_id, 0, MyKey2))
+
+print ("Syncing")
+client.syncUserData()
+
+print ("Retrieving removed removed data")
+print (client.getUserData(plane_id, 0, MyKey2))
+
+print ("Iterating over all user data entries and printing results")
+for i in range(client.getNumUserData(plane_id, 0)):
+  userDataId, key = client.getUserDataInfo(plane_id, 0, i)
+  print ("Info: (%s, %s)" % (userDataId, key))
+  print ("Value: %s" % client.getUserData(plane_id, 0, userDataId))
+
+print ("Removing body")
+client.removeBody(plane_id)
+
+print ("Retrieving user data")
+print (client.getUserData(plane_id, 0, MyKey1))
+print (client.getUserData(plane_id, 0, MyKey3))
+print (client.getUserData(plane_id, 0, MyKey4))
+
+print ("Syncing")
+client.syncUserData()
+
+print ("Retrieving user data")
+print (client.getUserData(plane_id, 0, MyKey1))
+print (client.getUserData(plane_id, 0, MyKey3))
+print (client.getUserData(plane_id, 0, MyKey4))
+
+plane_id2 = client.loadURDF(PLANE_PATH)
+print ("Plane1: %s, plane2: %s" % (plane_id, plane_id2))
+
+print ("Retrieving user data")
+print (client.getUserData(plane_id, 0, MyKey1))
+print (client.getUserData(plane_id, 0, MyKey3))
+print (client.getUserData(plane_id, 0, MyKey4))
+
diff --git a/examples/pybullet/pybullet.c b/examples/pybullet/pybullet.c
index e6c367935..bef819a0f 100644
--- a/examples/pybullet/pybullet.c
+++ b/examples/pybullet/pybullet.c
@@ -487,6 +487,21 @@ static PyObject* pybullet_connectPhysicsServer(PyObject* self, PyObject* args, P
 								sNumPhysicsClients++;
 					return  PyInt_FromLong(-1);
 				}
+
+				command = b3InitSyncUserDataCommand(sm);
+				statusHandle = b3SubmitClientCommandAndWaitStatus(sm, command);
+				statusType = b3GetStatusType(statusHandle);
+
+				if (statusType != CMD_SYNC_USER_DATA_COMPLETED)
+				{
+					printf("Connection terminated, couldn't get user data\n");
+					b3DisconnectSharedMemory(sm);
+							sm = 0;
+					sPhysicsClients1[freeIndex] = 0;
+								sPhysicsClientsGUI[freeIndex] = 0;
+								sNumPhysicsClients++;
+					return  PyInt_FromLong(-1);
+				}
 			}
 		} else
 		{
@@ -635,6 +650,249 @@ static PyObject* pybullet_syncBodyInfo(PyObject* self, PyObject* args, PyObject*
     return Py_None;
 }
 
+static PyObject* pybullet_syncUserData(PyObject* self, PyObject* args, PyObject* keywds)
+{
+	b3PhysicsClientHandle sm = 0;
+	int physicsClientId = 0;
+	static char* kwlist[] = {"physicsClientId", NULL};
+	b3SharedMemoryCommandHandle command;
+	b3SharedMemoryStatusHandle statusHandle;
+	int statusType;
+
+	if (!PyArg_ParseTupleAndKeywords(args, keywds, "|i", kwlist, &physicsClientId))
+	{
+		return NULL;
+	}
+	sm = getPhysicsClient(physicsClientId);
+	if (sm == 0)
+	{
+		PyErr_SetString(SpamError, "Not connected to physics server.");
+		return NULL;
+	}
+
+	command = b3InitSyncUserDataCommand(sm);
+	statusHandle = b3SubmitClientCommandAndWaitStatus(sm, command);
+	statusType = b3GetStatusType(statusHandle);
+
+	if (statusType != CMD_SYNC_USER_DATA_COMPLETED)
+	{
+		PyErr_SetString(SpamError, "Error in syncUserInfo command.");
+		return NULL;
+	}
+
+	Py_RETURN_NONE;
+}
+
+static PyObject* pybullet_addUserData(PyObject* self, PyObject* args, PyObject* keywds)
+{
+	b3PhysicsClientHandle sm = 0;
+	int physicsClientId = 0;
+	int bodyUniqueId = -1;
+	int linkIndex = -2;
+	const char* key = "";
+	const char* value = ""; // TODO: Change this to a PyObject and detect the type dynamically.
+
+	static char* kwlist[] = {"bodyUniqueId", "linkIndex", "key", "value", "physicsClientId", NULL};
+	b3SharedMemoryCommandHandle command;
+	b3SharedMemoryStatusHandle statusHandle;
+	int statusType;
+	int userDataId;
+	int valueLen=-1;
+
+	if (!PyArg_ParseTupleAndKeywords(args, keywds, "iiss|i", kwlist, &bodyUniqueId, &linkIndex, &key, &value, &physicsClientId))
+	{
+		return NULL;
+	}
+	sm = getPhysicsClient(physicsClientId);
+	if (sm == 0)
+	{
+		PyErr_SetString(SpamError, "Not connected to physics server.");
+		return NULL;
+	}
+
+	valueLen = strlen(value)+1;
+	command = b3InitAddUserDataCommand(sm, bodyUniqueId, linkIndex, key, USER_DATA_VALUE_TYPE_STRING, valueLen, value);
+	statusHandle = b3SubmitClientCommandAndWaitStatus(sm, command);
+	statusType = b3GetStatusType(statusHandle);
+
+	if (statusType != CMD_ADD_USER_DATA_COMPLETED)
+	{
+		PyErr_SetString(SpamError, "Error in addUserData command.");
+		return NULL;
+	}
+
+	userDataId = b3GetUserDataIdFromStatus(statusHandle);
+	return PyInt_FromLong(userDataId);
+}
+
+static PyObject* pybullet_removeUserData(PyObject* self, PyObject* args, PyObject* keywds)
+{
+	b3PhysicsClientHandle sm = 0;
+	int physicsClientId = 0;
+	int bodyUniqueId = -1;
+	int linkIndex = -1;
+	int userDataId = -1;
+
+	static char* kwlist[] = {"bodyUniqueId", "linkIndex", "userDataId",  "physicsClientId", NULL};
+	b3SharedMemoryCommandHandle command;
+	b3SharedMemoryStatusHandle statusHandle;
+	int statusType;
+
+	if (!PyArg_ParseTupleAndKeywords(args, keywds, "iii|i", kwlist, &bodyUniqueId, &linkIndex, &userDataId, &physicsClientId))
+	{
+		return NULL;
+	}
+	sm = getPhysicsClient(physicsClientId);
+	if (sm == 0)
+	{
+		PyErr_SetString(SpamError, "Not connected to physics server.");
+		return NULL;
+	}
+
+	command = b3InitRemoveUserDataCommand(sm, bodyUniqueId, linkIndex, userDataId);
+	statusHandle = b3SubmitClientCommandAndWaitStatus(sm, command);
+	statusType = b3GetStatusType(statusHandle);
+
+	if (statusType != CMD_REMOVE_USER_DATA_COMPLETED)
+	{
+		PyErr_SetString(SpamError, "Error in removeUserData command.");
+		Py_RETURN_FALSE;
+	}
+	Py_RETURN_TRUE;
+}
+
+
+static PyObject* pybullet_getUserDataId(PyObject* self, PyObject* args, PyObject* keywds)
+{
+	b3PhysicsClientHandle sm = 0;
+	int physicsClientId = 0;
+	int bodyUniqueId = -1;
+	int linkIndex = -1;
+	const char* key = "";
+	int userDataId;
+
+	
+
+
+	static char* kwlist[] = {"bodyUniqueId", "linkIndex", "key",  "physicsClientId", NULL};
+	
+	if (!PyArg_ParseTupleAndKeywords(args, keywds, "iis|i", kwlist, &bodyUniqueId, &linkIndex, &key, &physicsClientId))
+	{
+		return NULL;
+	}
+	sm = getPhysicsClient(physicsClientId);
+	if (sm == 0)
+	{
+		PyErr_SetString(SpamError, "Not connected to physics server.");
+		return NULL;
+	}
+
+	userDataId = b3GetUserDataId(sm, bodyUniqueId, linkIndex, key);
+	return PyInt_FromLong(userDataId);
+}
+
+static PyObject* pybullet_getUserData(PyObject* self, PyObject* args, PyObject* keywds)
+{
+	b3PhysicsClientHandle sm = 0;
+	int physicsClientId = 0;
+	int bodyUniqueId = -1;
+	int linkIndex = -1;
+	int userDataId = -1;
+
+	static char* kwlist[] = {"bodyUniqueId", "linkIndex", "userDataId",  "physicsClientId", NULL};
+
+
+
+	struct b3UserDataValue value;
+	if (!PyArg_ParseTupleAndKeywords(args, keywds, "iii|i", kwlist, &bodyUniqueId, &linkIndex, &userDataId, &physicsClientId))
+	{
+		return NULL;
+	}
+	sm = getPhysicsClient(physicsClientId);
+	if (sm == 0)
+	{
+		PyErr_SetString(SpamError, "Not connected to physics server.");
+		return NULL;
+	}
+
+
+	if (!b3GetUserData(sm, bodyUniqueId, linkIndex, userDataId, &value)) {
+		Py_RETURN_NONE;
+	}
+	switch (value.m_type) {
+		case USER_DATA_VALUE_TYPE_STRING:
+			return PyString_FromString((const char *)value.m_data1);
+		default:
+			PyErr_SetString(SpamError, "User data value has unknown type");
+			return NULL;
+	}
+}
+
+static PyObject* pybullet_getNumUserData(PyObject* self, PyObject* args, PyObject* keywds)
+{
+	b3PhysicsClientHandle sm = 0;
+	int physicsClientId = 0;
+	int bodyUniqueId = -1;
+	int linkIndex = -1;
+
+	static char* kwlist[] = {"bodyUniqueId", "linkIndex",  "physicsClientId", NULL};
+
+
+
+	int numUserData;
+
+	if (!PyArg_ParseTupleAndKeywords(args, keywds, "ii|i", kwlist, &bodyUniqueId, &linkIndex, &physicsClientId))
+	{
+		return NULL;
+	}
+	sm = getPhysicsClient(physicsClientId);
+	if (sm == 0)
+	{
+		PyErr_SetString(SpamError, "Not connected to physics server.");
+		return NULL;
+	}
+
+	numUserData = b3GetNumUserData(sm, bodyUniqueId, linkIndex);
+	return PyInt_FromLong(numUserData);
+}
+
+static PyObject* pybullet_getUserDataInfo(PyObject* self, PyObject* args, PyObject* keywds)
+{
+	b3PhysicsClientHandle sm = 0;
+	int physicsClientId = 0;
+	int bodyUniqueId = -1;
+	int linkIndex = -1;
+	int userDataIndex = -1;
+
+	static char* kwlist[] = {"bodyUniqueId", "linkIndex", "userDataIndex", "physicsClientId", NULL};
+
+
+	const char* key = 0;
+	int userDataId = -1;
+
+	if (!PyArg_ParseTupleAndKeywords(args, keywds, "iii|i", kwlist, &bodyUniqueId, &linkIndex, &userDataIndex, &physicsClientId))
+	{
+		return NULL;
+	}
+	sm = getPhysicsClient(physicsClientId);
+	if (sm == 0)
+	{
+		PyErr_SetString(SpamError, "Not connected to physics server.");
+		return NULL;
+	}
+
+	b3GetUserDataInfo(sm, bodyUniqueId, linkIndex, userDataIndex, &key, &userDataId);
+	if (key == 0 || userDataId == -1) {
+		PyErr_SetString(SpamError, "Could not get user data info.");
+		Py_RETURN_NONE;
+	}
+	{
+		PyObject *userDataInfoTuple = PyTuple_New(2);
+		PyTuple_SetItem(userDataInfoTuple, 0, PyInt_FromLong(userDataId));
+		PyTuple_SetItem(userDataInfoTuple, 1, PyString_FromString(key));
+		return userDataInfoTuple;
+	}
+}
 
 static PyObject* pybullet_saveWorld(PyObject* self, PyObject* args, PyObject* keywds)
 {
@@ -6485,6 +6743,7 @@ static PyObject* pybullet_createMultiBody(PyObject* self, PyObject* args, PyObje
 	int baseCollisionShapeIndex=-1;
 	int baseVisualShapeIndex=-1;
 	int useMaximalCoordinates = 0;
+	int flags = -1;
 	PyObject* basePosObj=0;
 	PyObject* baseOrnObj=0;
 	PyObject* baseInertialFramePositionObj=0;
@@ -6500,21 +6759,22 @@ static PyObject* pybullet_createMultiBody(PyObject* self, PyObject* args, PyObje
 	PyObject* linkJointAxisObj=0;
 	PyObject* linkInertialFramePositionObj=0;
 	PyObject* linkInertialFrameOrientationObj=0;
+		
+	static char* kwlist[] = {
+		"baseMass","baseCollisionShapeIndex","baseVisualShapeIndex","basePosition", "baseOrientation", 
+		"baseInertialFramePosition", "baseInertialFrameOrientation",	"linkMasses","linkCollisionShapeIndices", 
+		"linkVisualShapeIndices","linkPositions", "linkOrientations","linkInertialFramePositions","linkInertialFrameOrientations", 		"linkParentIndices", 
+		"linkJointTypes","linkJointAxis", "useMaximalCoordinates", "flags", "physicsClientId", NULL};
 
-	static char* kwlist[] = {"baseMass","baseCollisionShapeIndex","baseVisualShapeIndex","basePosition", "baseOrientation", "baseInertialFramePosition", "baseInertialFrameOrientation",
-		"linkMasses","linkCollisionShapeIndices", "linkVisualShapeIndices",
-		"linkPositions", "linkOrientations","linkInertialFramePositions","linkInertialFrameOrientations", "linkParentIndices", "linkJointTypes","linkJointAxis", 
-		"useMaximalCoordinates","physicsClientId", NULL};
-
-	if (!PyArg_ParseTupleAndKeywords(args, keywds, "|diiOOOOOOOOOOOOOOii", kwlist, &baseMass,&baseCollisionShapeIndex,&baseVisualShapeIndex,
-				&basePosObj, &baseOrnObj,&baseInertialFramePositionObj, &baseInertialFrameOrientationObj,
-		&linkMassesObj, &linkCollisionShapeIndicesObj, &linkVisualShapeIndicesObj, &linkPositionsObj, &linkOrientationsObj,
-		&linkInertialFramePositionObj, &linkInertialFrameOrientationObj,
-		&linkParentIndicesObj, &linkJointTypesObj,&linkJointAxisObj,
-		&useMaximalCoordinates, &physicsClientId))
+	if (!PyArg_ParseTupleAndKeywords(args, keywds, "|diiOOOOOOOOOOOOOOiii", kwlist, 
+		&baseMass,&baseCollisionShapeIndex,&baseVisualShapeIndex,&basePosObj, &baseOrnObj,
+		&baseInertialFramePositionObj, &baseInertialFrameOrientationObj,&linkMassesObj, &linkCollisionShapeIndicesObj, 
+		&linkVisualShapeIndicesObj, &linkPositionsObj, &linkOrientationsObj,&linkInertialFramePositionObj, &linkInertialFrameOrientationObj,&linkParentIndicesObj, 
+		&linkJointTypesObj,&linkJointAxisObj, &useMaximalCoordinates, &flags, &physicsClientId))
 	{
 		return NULL;
 	}
+
 	sm = getPhysicsClient(physicsClientId);
 	if (sm == 0)
 	{
@@ -6634,6 +6894,10 @@ static PyObject* pybullet_createMultiBody(PyObject* self, PyObject* args, PyObje
 			{
 				b3CreateMultiBodyUseMaximalCoordinates(commandHandle);
 			}
+			if (flags >0)
+			{
+				b3CreateMultiBodySetFlags(commandHandle, flags);
+			}
 			statusHandle = b3SubmitClientCommandAndWaitStatus(sm, commandHandle);
 			statusType = b3GetStatusType(statusHandle);
 			if (statusType == CMD_CREATE_MULTI_BODY_COMPLETED)
@@ -8172,12 +8436,12 @@ static PyObject* pybullet_calculateInverseKinematics(PyObject* self,
 			}
 			else
 			{
+				int szInBytes = sizeof(double) * szJointDamping;
+				int i;
 				if (szJointDamping != dofCount)
 				{
 					printf("calculateInverseKinematics: the size of input joint damping values should be equal to the number of degrees of freedom, ignoring the additonal values.");
 				}
-				int szInBytes = sizeof(double) * szJointDamping;
-				int i;
 				jointDamping = (double*)malloc(szInBytes);
 				for (i = 0; i < szJointDamping; i++)
 				{
@@ -8821,6 +9085,34 @@ static PyMethodDef SpamMethods[] = {
         "syncBodyInfo(physicsClientId=0)\n"
         "Update body and constraint/joint information, in case other clients made changes."},
     
+	{"syncUserData", (PyCFunction)pybullet_syncUserData, METH_VARARGS | METH_KEYWORDS,
+	 "syncUserData(physicsClientId=0)\n"
+	 "Update user data, in case other clients made changes."},
+
+	{"addUserData", (PyCFunction)pybullet_addUserData, METH_VARARGS | METH_KEYWORDS,
+	 "addUserData(bodyUniqueId, linkIndex, key, value, physicsClientId=0)\n"
+	 "Adds or updates a user data entry to a link. Returns user data identifier."},
+
+	{"getUserData", (PyCFunction)pybullet_getUserData, METH_VARARGS | METH_KEYWORDS,
+	 "getUserData(bodyUniqueId, linkIndex, userDataId, physicsClientId=0)\n"
+	 "Returns the user data value."},
+
+	{"removeUserData", (PyCFunction)pybullet_removeUserData, METH_VARARGS | METH_KEYWORDS,
+	 "removeUserData(bodyUniqueId, linkIndex, userDataId, physicsClientId=0)\n"
+	 "Removes a user data entry."},
+
+	{"getUserDataId", (PyCFunction)pybullet_getUserDataId, METH_VARARGS | METH_KEYWORDS,
+	 "getUserDataId(bodyUniqueId, linkIndex, key, physicsClientId=0)\n"
+	 "Retrieves the userDataId on a link given the key."},
+
+	{"getNumUserData", (PyCFunction)pybullet_getNumUserData, METH_VARARGS | METH_KEYWORDS,
+	 "getNumUserData(bodyUniqueId, linkIndex, physicsClientId=0)\n"
+	 "Retrieves the number of user data entries in a link."},
+
+	{"getUserDataInfo", (PyCFunction)pybullet_getUserDataInfo, METH_VARARGS | METH_KEYWORDS,
+	 "getUserDataInfo(bodyUniqueId, linkIndex, userDataIndex, physicsClientId=0)\n"
+	 "Retrieves the key and the identifier of a user data as (id, key)."},
+
 	{"removeBody", (PyCFunction)pybullet_removeBody, METH_VARARGS | METH_KEYWORDS,
 	 "Remove a body by its body unique id."},
 
diff --git a/src/LinearMath/btHashMap.h b/src/LinearMath/btHashMap.h
index 5e9cdb605..f43e76a80 100644
--- a/src/LinearMath/btHashMap.h
+++ b/src/LinearMath/btHashMap.h
@@ -30,6 +30,11 @@ struct btHashString
 		return m_hash;
 	}
 
+	btHashString()
+	{
+		m_string="";
+		m_hash=0;
+	}
 	btHashString(const char* name)
 		:m_string(name)
 	{