Custom user types

I am writing this on behalf of a fraternity that I am involved with. We are currently redoing the website, and I was wondering if there is a way to create custom user types with different permissions using wordpress. Other than the standard admins and things like that. We would like to have three categories for members (pledges, brothers, and alumni). We would also like for there to be a way to easily change a members status (i.e. pledge to brother, brother to alumni).