The Groups addon allows you to share projects (folders) between users with precise controls.
Share with Roles
This added functionality allows administrators to assign all users of a certain role read, write, or delete permissions to a folder. (Controlled from “Documents > Folders”)
Add a Specific Person to This Folder
This area gives administrators the ability to assign read, write, or delete permissions to individual users. (Controlled from “Documents > Folders”)
When BuddyPress is enabled, users can create groups. When activated, this plugin will detect all groups available, and will let the administrators decide whether or not they want to share a project with a group.