[agoratim]

Doesn't quite do what I'm looking for but you did give me an idea so thank you!

One thing I didn't mention from above is that the private forums and usergroups are being created and destroyed by an external system rather than being done by hand. The number of private forums will exceed several thousand and each will have an associated usergroup that has access to it.

amykhar,
Your suggestion was a good one but the real problem is that whenever I create a new forum and usergroup I need the existing forums to remain private to the new group. So if private forums for Group A already exist and I create Group B I don't want Group B to automatically have access to Group A's private forums. The situtation gets worse when I have a thousand groups that I would need to update simply because I created a new private forum.

Any suggestions?
Thanks