I've been using Boost for several months now, and I must say I've been very happy with it. I've primarily been using the threads and regex stuff from the library, and I have a question regarding the behavior of the thread_group.join_all method. In my current situation, I have a thread_group which launches several threads of execution for background servers, on an as-needed basis. If it becomes necessary to shutdown those background servers, I issue a join_all on the thread_group to wait for all activity to cease, then I can clear up the server instances themselves. If I issue a join_all from a thread and, while waiting for the join_all to exit, another thread creates a thread within my thread_group, what is expected? Will the join_all now wait for the original threads, as well as the newcomer, or will it only wait on the threads which were running at the time the join_all was called?? Thanx, Steve Dussinger