There are the following synchronization services:
| Group | Elements | 
| Critical section services | Begin_Critical_Section, Call_When_Not_Critical, Cancel_Call_When_Not_Critical, Claim_Critical_Section, CritSecCallback, End_Crit_And_Suspend, End_Critical_Section, Get_Crit_Section_Status, Get_Crit_Status_No_Block, Get_Crit_Status_Thread, Release_Critical_Section | 
| Must-complete section services | _EnterMustComplete, _ExecIntMustComplete, _ExecVxDIntMustComplete, _LeaveMustComplete, _ResumeExecMustComplete | 
| Semaphore services | Create_Semaphore, Destroy_Semaphore, Signal_Semaphore, Signal_Semaphore_No_Switch, Wait_Semaphore | 
| Mutex services | _CreateMutex, _DestroyMutex, _EnterMutex, _GetMutexOwner, _LeaveMutex | 
| Thread blocking services | _BlockOnID, _SignalID |