diff --git a/reactos/ntoskrnl/ntoskrnl.def b/reactos/ntoskrnl/ntoskrnl.def
index 973ef319b0d..9f28ae38605 100644
--- a/reactos/ntoskrnl/ntoskrnl.def
+++ b/reactos/ntoskrnl/ntoskrnl.def
@@ -508,6 +508,8 @@ Ke386CallBios@8
 Ke386IoSetAccessProcess@8
 Ke386QueryIoAccessMap@8
 Ke386SetIoAccessMap@8
+@KeAcquireGuardedMutex@4
+@KeAcquireGuardedMutexUnsafe@4
 KeAcquireSpinLockAtDpcLevel@4
 @KeAcquireDispatcherDatabaseLockAtDpcLevel@0
 @KeAcquireInStackQueuedSpinLockAtDpcLevel@8
@@ -529,6 +531,7 @@ KeDeregisterBugCheckReasonCallback@4
 KeDetachProcess@0
 KeDisconnectInterrupt@4
 KeEnterCriticalRegion@0
+KeEnterGuardedRegion@0
 KeEnterKernelDebugger@0
 KeFindConfigurationEntry@16
 KeFindConfigurationNextEntry@20
@@ -552,6 +555,7 @@ KeInitializeApc@32
 KeInitializeDeviceQueue@4
 KeInitializeDpc@12
 KeInitializeEvent@12
+@KeInitializeGuardedMutex@4
 KeInitializeInterrupt@44
 KeInitializeMutant@8
 KeInitializeMutex@8
@@ -569,6 +573,7 @@ KeInsertQueueDpc@12
 KeIsAttachedProcess@0
 KeIsExecutingDpc@0
 KeLeaveCriticalRegion@0
+KeLeaveGuardedRegion@0
 KeLoaderBlock DATA
 KeNumberProcessors DATA
 KeProfileInterrupt@4
@@ -591,6 +596,8 @@ KeReadStateTimer@4
 KeRegisterBugCheckCallback@20
 KeRegisterBugCheckReasonCallback@16
 @KeReleaseDispatcherDatabaseLockFromDpcLevel@0
+@KeReleaseGuardedMutexUnsafe@4
+@KeReleaseGuardedMutex@4
 @KeReleaseInStackQueuedSpinLockFromDpcLevel@4
 KeReleaseInterruptSpinLock@8
 KeReleaseMutant@16
@@ -633,6 +640,7 @@ KeStackAttachProcess@8
 KeSynchronizeExecution@12
 KeTerminateThread@4
 KeTickCount DATA
+@KeTryToAcquireGuardedMutex@4
 KeUpdateRunTime@8
 KeUpdateSystemTime@8
 KeUnstackDetachProcess@4
diff --git a/reactos/w32api/include/ddk/winddk.h b/reactos/w32api/include/ddk/winddk.h
index eff7c342b4b..3c5e97be4e7 100644
--- a/reactos/w32api/include/ddk/winddk.h
+++ b/reactos/w32api/include/ddk/winddk.h
@@ -5350,6 +5350,52 @@ RtlxUnicodeStringToAnsiSize(
 #endif
 
 
+/* Guarded Mutex routines */
+
+VOID 
+FASTCALL
+KeAcquireGuardedMutex(
+    PKGUARDED_MUTEX GuardedMutex
+);
+
+VOID
+FASTCALL
+KeAcquireGuardedMutexUnsafe(
+    PKGUARDED_MUTEX GuardedMutex
+);
+
+VOID 
+STDCALL
+KeEnterGuardedRegion(VOID);
+
+VOID
+STDCALL
+KeLeaveGuardedRegion(VOID);
+
+VOID 
+FASTCALL
+KeInitializeGuardedMutex(
+    PKGUARDED_MUTEX GuardedMutex
+);
+
+VOID 
+FASTCALL
+KeReleaseGuardedMutexUnsafe(
+    PKGUARDED_MUTEX GuardedMutex
+);
+
+VOID 
+FASTCALL
+KeReleaseGuardedMutex(
+    PKGUARDED_MUTEX GuardedMutex
+);
+
+BOOL 
+FASTCALL
+KeTryToAcquireGuardedMutex(
+    PKGUARDED_MUTEX GuardedMutex
+);
+
 /** Executive support routines **/
 
 NTOSAPI