Hi, there are currently two ways to support multiple user collaboration.
One is to use our standard file-sharing feature. You can share a folder with full-access right to your colleagues / friends. Please note they must also have a DriveHQ account in order to use the collaboration features. Your friends can logon DriveHQ.com with their own username and password. They should see a special folder: "DriveHQ Share". Folders you shared to him are placed in this folder. You can share folders with different permissions to different users.
The other collaboration is even better. You can use our Group Account feature. By upgrading to a group account, you can create/manage your sub-accounts. The system also automatically creates two shared folders: GroupRead and GroupWrite. These two folderes are accessible to all your group members with "read" and "read/write" permissions as the name suggests.
One final note: if multiple users are editing the same file at exactly the same time, that could cause some problem. They could overwrite changes made by other users.