Your 'Manage Staff' module is where you can add staff and assign them user roles. When staff are added, you can change their details or access levels by returning to Manage Staff and editing the user.
Staff can be added as Administrators, Office Staff or Engineers. The differences are as follows:
Admin Account Level
Administrators have all access to all areas (excluding editing Master User Accounts). Administrators should only be assigned to the people involved in running your business, such as Business Partners or other Directors.
Office Staff Level
Office Staff Access Levels have been set so that your staff in the office can see what they need to but they can't change the account settings etc whereas Admins can. Office Staff can see all diaries, staff, invoices, parts, job history lists and Technical Library.
This is the basic level requirement needed for your staff on the road to carry out their jobs effectively. They do not have access to anything other than their own diary, daily workload and Technical Library.