diff --git a/include/loki/LevelMutex.h b/include/loki/LevelMutex.h
index 1c33af9..d585d54 100644
--- a/include/loki/LevelMutex.h
+++ b/include/loki/LevelMutex.h
@@ -51,6 +51,7 @@
 #endif
 
 #include <loki/ThreadLocal.h> // Include Loki's form of thread_local declaration.
+#include <loki/Checker.h> // Needed to check class invariants.
 
 #if !defined( LOKI_THREAD_LOCAL )
     #warning "Your compiler will not allow Loki::LevelMutex."
@@ -264,26 +265,12 @@ public:
 
 protected:
 
-    /** @class Checker Performs validity check on mutex to insure no class invariants
-     were violated inside any member function.  This class only gets used in debug
-     builds, and any instance of it gets optimized away in release builds.  A checker
-     is created inside many of member functions so that it's destructor gets called
-     when the function exits.  It determines if any class invariants were violated
-     during the function call.
+    /** @note CheckFor performs validity checking in many functions to determine if the
+     code violated any invariants, if any content changed, or if the function threw an
+     exception. The checkers only get used in debug builds, and get optimized away in
+     release builds.
      */
-    class Checker
-    {
-    public:
-        inline explicit Checker( const volatile LevelMutexInfo * mutex ) :
-            m_mutex( mutex ) { Check(); }
-        inline ~Checker( void ) { Check(); }
-        inline bool Check( void ) const { return m_mutex->IsValid(); }
-    private:
-        Checker( void );
-        Checker( const Checker & );
-        Checker & operator = ( const Checker & );
-        const volatile LevelMutexInfo * m_mutex;
-    };
+    typedef ::Loki::CheckFor< LevelMutexInfo > CheckFor;
 
     /** @class MutexUndoer
      Undoes actions by MultiLock if an exception occurs.  It keeps track of
@@ -778,7 +765,7 @@ public:
 
     virtual MutexErrors::Type TryLock( void ) volatile
     {
-        LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+        LOKI_MUTEX_DEBUG_CODE( CheckFor::Invariants checker( this, &IsValid() ); (void)checker; )
 
         MutexErrors::Type result = LevelMutexInfo::PreLockCheck( true );
         if ( MutexErrors::Success == result )
@@ -799,7 +786,7 @@ public:
 
     virtual MutexErrors::Type Lock( void ) volatile
     {
-        LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+        LOKI_MUTEX_DEBUG_CODE( CheckFor::Invariants checker( this, &IsValid() ); (void)checker; )
 
         MutexErrors::Type result = LevelMutexInfo::PreLockCheck( false );
         if ( MutexErrors::Success == result )
@@ -818,7 +805,7 @@ public:
 
     virtual MutexErrors::Type Lock( unsigned int milliSeconds ) volatile
     {
-        LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+        LOKI_MUTEX_DEBUG_CODE( CheckFor::Invariants checker( this, &IsValid() ); (void)checker; )
 
         MutexErrors::Type result = LevelMutexInfo::PreLockCheck( false );
         if ( MutexErrors::Success == result )
@@ -853,7 +840,7 @@ public:
 
     virtual MutexErrors::Type Unlock( void ) volatile
     {
-        LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+        LOKI_MUTEX_DEBUG_CODE( CheckFor::Invariants checker( this, &IsValid() ); (void)checker; )
 
         MutexErrors::Type result = LevelMutexInfo::PreUnlockCheck();
         if ( MutexErrors::Success == result )
@@ -898,7 +885,7 @@ private:
      */
     virtual MutexErrors::Type LockThis( void ) volatile
     {
-        LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+        LOKI_MUTEX_DEBUG_CODE( CheckFor::Invariants checker( this, &IsValid() ); (void)checker; )
         assert( this != LevelMutexInfo::GetCurrentMutex() );
 
         const MutexErrors::Type result = m_mutex.Lock();
@@ -918,7 +905,7 @@ private:
      */
     virtual MutexErrors::Type LockThis( unsigned int milliSeconds ) volatile
     {
-        LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+        LOKI_MUTEX_DEBUG_CODE( CheckFor::Invariants checker( this, &IsValid() ); (void)checker; )
 
         clock_t timeOut = clock() + milliSeconds;
         while ( clock() < timeOut )
@@ -943,7 +930,7 @@ private:
      */
     virtual MutexErrors::Type UnlockThis( void ) volatile
     {
-        LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+        LOKI_MUTEX_DEBUG_CODE( CheckFor::Invariants checker( this, &IsValid() ); (void)checker; )
         assert( NULL != LevelMutexInfo::GetCurrentMutex() );
 
         if ( 1 < LevelMutexInfo::GetLockCount() )
diff --git a/src/LevelMutex.cpp b/src/LevelMutex.cpp
index ff8f760..c500e52 100644
--- a/src/LevelMutex.cpp
+++ b/src/LevelMutex.cpp
@@ -417,7 +417,7 @@ MutexErrors::Type LevelMutexInfo::MultiLock( MutexContainer & mutexes,
 
     if ( 0 == milliSeconds )
         return MultiLock( mutexes );
-    
+
     const std::size_t count = mutexes.size();
     if ( 0 == count )
         return MutexErrors::EmptyContainer;
@@ -592,7 +592,7 @@ void LevelMutexInfo::DecrementCount( void ) volatile
 
 bool LevelMutexInfo::IsLockedByCurrentThread( void ) const volatile
 {
-    LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+    LOKI_MUTEX_DEBUG_CODE( CheckFor::NoChangeOrThrow checker( this, &IsValid() ); (void)checker; )
 
     if ( !IsLocked() )
         return false;
@@ -610,7 +610,7 @@ bool LevelMutexInfo::IsLockedByCurrentThread( void ) const volatile
 
 bool LevelMutexInfo::IsRecentLock( void ) const volatile
 {
-    LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+    LOKI_MUTEX_DEBUG_CODE( CheckFor::NoChangeOrThrow checker( this, &IsValid() ); (void)checker; )
 
     if ( 0 == m_count )
         return false;
@@ -631,7 +631,7 @@ bool LevelMutexInfo::IsRecentLock( void ) const volatile
 
 bool LevelMutexInfo::IsRecentLock( std::size_t count ) const volatile
 {
-    LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+    LOKI_MUTEX_DEBUG_CODE( CheckFor::NoChangeOrThrow checker( this, &IsValid() ); (void)checker; )
 
     if ( 0 == count )
         return false;
@@ -651,7 +651,7 @@ bool LevelMutexInfo::IsRecentLock( std::size_t count ) const volatile
 
 bool LevelMutexInfo::IsLockedByAnotherThread( void ) const volatile
 {
-    LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+    LOKI_MUTEX_DEBUG_CODE( CheckFor::NoChangeOrThrow checker( this, &IsValid() ); (void)checker; )
 
     if ( !IsLocked() )
         return false;
@@ -666,7 +666,7 @@ bool LevelMutexInfo::IsLockedByAnotherThread( void ) const volatile
 
 void LevelMutexInfo::PostLock( void ) volatile
 {
-    LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+    LOKI_MUTEX_DEBUG_CODE( CheckFor::NoThrow checker( this, &IsValid() ); (void)checker; )
     assert( 0 == m_count );
     assert( nullptr == m_previous );
     assert( this != s_currentMutex );
@@ -681,7 +681,7 @@ void LevelMutexInfo::PostLock( void ) volatile
 
 void LevelMutexInfo::PreUnlock( void ) volatile
 {
-    LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+    LOKI_MUTEX_DEBUG_CODE( CheckFor::NoThrow checker( this, &IsValid() ); (void)checker; )
     assert( 1 == m_count );
     assert( nullptr != s_currentMutex );
     assert( this == s_currentMutex );
@@ -696,7 +696,7 @@ void LevelMutexInfo::PreUnlock( void ) volatile
 
 MutexErrors::Type LevelMutexInfo::PreLockCheck( bool forTryLock ) volatile
 {
-    LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+    LOKI_MUTEX_DEBUG_CODE( CheckFor::NoThrow checker( this, &IsValid() ); (void)checker; )
 
     const unsigned int currentLevel = GetCurrentThreadsLevel();
     if ( currentLevel < LevelMutexInfo::GetLevel() )
@@ -730,7 +730,7 @@ MutexErrors::Type LevelMutexInfo::PreLockCheck( bool forTryLock ) volatile
 
 MutexErrors::Type LevelMutexInfo::PreUnlockCheck( void ) volatile
 {
-    LOKI_MUTEX_DEBUG_CODE( Checker checker( this ); (void)checker; )
+    LOKI_MUTEX_DEBUG_CODE( CheckFor::NoThrow checker( this, &IsValid() ); (void)checker; )
 
     if ( 0 == m_count )
         return MutexErrors::WasntLocked;