Multiple Role Membership

Hello,
I need to populate a dropdown list with users who match certain role criteria. For example, if I have the following roles: Manager, Employee, Supervisor I would like to populate the list with only the Manager and Employee roles. Some individuals have multiple roles and they should be excluded if they also have the Supervisor role as illustrated below:


Name: A , Role(s): Manager, Employee, Supervisor
Name: B, Role(s): Employee
Name: C, Role(s): Manager, Employee


The final list should only contain names B & C.


I can use Roles.GetUsersInRole("Employee") but I am not sure if this is efficient or not.


thanks in advance,
mitch
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