[Jeff Sayre]

In other words, as jjj is saying, search the forum for threads on “deep integration”.

https://buddypress.org/forums/search.php?q=deep+integration

I’m not sure if this is still accurate, but you can also give this a try:

http://theeasybutton.com/blog/2009/07/17/integrating-buddypress-wordpress-mu-and-bbpress/