[@plrk Participant 15 years, 8 months ago]

bbPress does not have any native ways to hide forums that should be hidden. You can do as I have done – installing a “blank” theme that redirects users to your main site, limiting users to use the built-in group forums functionality only – or you could install a bbPress plugin that hides forums from those that are not allowed to view them. There is such a plugin, intended specifically for buddypress users, but I can’t remember what it is called.