Hello Zaxo, thanks for the reply. I tried the negative pid idea, but that does not appear to be implemented in Windows. I have been looking into ActiveStates pseudo-fork(), which claims a kill of the parent process will clean up all child processes, but fork is a whole new can of worms I would rather avoid by using Open3. I would be happy to use your code snippet, but I am not able to retrieve the pids that are spawned inside the CMD.exe which is spawned from Open3. Know any tricks for that? A real ugly way would be taking PS snapshots and seeing what pids were created in the meantime, but you could end up killing things you down want to. Thanks, Steve