On a related note, I recently implemented a System.Process library on Unix. Source code attached. The Windows implementation should be relatively straightforward. Porting it to Hugs will require System.Posix.forkProcess, but I don't see any great difficulties there. One warning: if you want to use it in a concurrent environment with GHC, you need to use GHC's threaded RTS (i.e. use the -threaded option in the forthcoming GHC 6.2.1), otherwise waitForProcess will block all threads. POpen-type abstractions can easily be layered on top of the functionality here - indeed the library should probably contain some higher-level versions which correspond to common usage. I think this is a good platform-independent abstraction for process management. What do others think? Cheers, Simon