To create a User that will only have access to a certain account or a selection of several accounts, use the following procedure to create a user with special account level permissions:
Go to 'User management' under the administration dropdown located at the top right of the screen and select the 'Users' tab
Click "create user" and provide a login name in the 'Username' field, a valid 'E-mail' address, and a 'Password' of at least 8 characters
From the 'Group' dropdown box, select the 'Group' you want to associate to this users
Next, click the 'Account Access' tab, and select the 'Access Type' for this user:
Grant access to all accounts - to provide access to any of the available accounts in the system
Grant access to only specific accounts - to only provide access to usage and charge data of specific accounts
If you've selected Grant access to only specific accounts, then select from the Account Access list, each Account Name where this user should have access for. You may select a top level account, or an account further down in the hierarchy. Account inheritance is applicable, meaning lower level accounts are automatically included when selecting a top level account. If there are multiple reports, select the corresponding report from the drop down list first, before selecting any accounts.
When all fields have been filled in, you may create the user by clicking the 'Save' button.