In Accreditation Manager you can have multiple sites. You can think of these as physical locations. Sites can be created by NAPT Support staff.
When you create a Lead, you can assign a set of permissions to a site. This allows you to create several different scenarios. Here is an example of a potential scenario.
Example 1: Your organization has three sites: Minneapolis, Dallas, and Orlando.
Lead #1: This lead should have access to all items in your organization. To accomplish this, create a new lead and enable as a global admin.
Lead #2: This lead should have access to all audits, in all locations, but access to no other items. To accomplish this, create a new Permission called "Audit Only". 
When you create Lead #2, you should add go to the Sites and Permissions tab and select each site and assign it to the Audith Only role. You would repeat this for each site.
Lead #3: This lead should have access to all items, except settings, in Dallas. There is a pre-build role called "Power User (No Settings)" so you do not need to create any additional roles. When you create the new Lead, all you need to do is make sure to seelct the Dallas Site and the Power User role.