For a couple of projects we needed to add a forum to a WordPress site. We started off with bbPress based on advice of WordPress experts I got during the preparation phase.
Once started we ran in some things that the client wanted and we could not accomplish with bbPress.

Looking at the information I gathered during the preparation phase I decided to give Simple:Press a good test. It worked really good. We created a separate theme to incorporate some changes our clients wanted. The developers of Simple:Press even added a class to the user-groups in the latest update so we could hide the admins in the members view.

To make it easy for the clients I created an Owners Guide on how to start the forum, start a user group, start a group, start a forum, topic, reply and more.

To make it even easier for the owners of the forum I also created an User Guide so they can distribute it to the members of their forum.

These are closed (paid) forums.

You can find an article about it here Membership program with a forum? WordPress and Simple:Press and you can even download the users guide and owners manual for free from this article.

Hope you like it.