While in Basecamp classic you were able to mark todo-lists or messages as private (only visible by your company), it seems that there's no such feature in the "all-new" version of Basecamp. I know ...
What web-based software combines bug tracking, agile project management and client collaboration? [duplicate]
Possible Duplicate: What are project managing, task/issue/time tracking web apps are available for free or at least cheap enough? I'm aware of really good packages that handle each one ...