When you purchase a subscription to The Rehab Lab, you are provided with a single username and password which all users enter to access the software.
A single-user subscription allows for one user to be logged into your profile at any one time; a 2-user subscription allows for any 2-users at your location to be logged into The Rehab Lab simultaneously; and so on.
When you purchase a multi-location subscription, each 'location' will be provided their own username and password that all users at that location will use to access their profile.