Set up user accounts for everyone who needs to access RB9. Store work-related and personal information about them. Give them user names and initial passwords to access RB9. (After logging in, users can create their own passwords in Change Password. Or set a new password at log-in anytime if they forget it.)
Assign users to security groups that give them permissions to only the actions they need to perform. Individual users can be members of multiple security groups, so if you have employees whose responsibilities overlap different areas, such as someone who oversees both calendaring and billing, you can give that person access to both areas through membership in different security groups.
You can also assign users to message groups, so you can send a message to all the members of a group simultaneously.
If a user forgets their password, administrators do not have a way to retrieve the password, but can reset the user's password for them. See Resetting passwords.