A question that has been in my mind for several years now, is what 'groups', specifically, does Obama belong?

Bill Clinton was a Rhodes Scholar, and was mentored by Carrol Quigley, and had memberships in various organizations, the Trilateral Commission comes to mind. It is interesting to note, that relatively little information regarding Obama's 'social networking' has remained somewhat sparse.

Does anyone here know of, or possess information regarding this question?