Usually a 2-3 interview experience (seems to lean more to 2). Starts with the supervisor over you and then if you are called back for a 2nd interview you will have 2-4 people who are usually other managers from similar programs, or key staff in your program. They also try to have the director in on most final interviews as they are very interested in keeping a cohesive positive team and want to see that you will be able to fit in with this.