[chrishajer]

Well – you can have specific forums restricted to certain users right now with a plugin. It’s easier than using .htaccess.

https://bbpress.org/plugins/topic/hidden-forums/

That’s not what you asked initially though.

require a password before someone can register and see the forum

Both are possible, the first request just doesn’t make any sense unless there will be a company wide memo with the username and password on it. If it’s truly for internal use only, just put it on an intranet rather than the Internet, or use .htaccess to restrict by IP address rather than passwords. If you have a fixed range of IP addresses, you could allow only those to access the bbPress forum.

You can do both.