The Account screen lists all the users on your account. These users are permitted to view any of the maps on the account. You can add or remove users at any time as long as the total number of users is never more than the number of users on your subscription. See the Upgrade/Downgrade button described on the Account screen to increase or decrease this number of users you are paying for.
Add a User
Click the Add New User button and enter the new user's email address. See How to Add a New User for more information.
Delete a User
Click "Delete User." See How to Remove a User for more information.
By default a new user can only view your maps. To grant other permissions click User Permissions on the map menu.
The general rule on who can view your maps is that any users listed on your account can view any maps on your account. But it is also possible to grant users on other accounts access to certain maps. See the "Outsider Access" section of the Map Properties screen for more information.