I had an interview there last year! Basically they sat us in a room at tables with an older student and we talked for a little it. Then they started the program and brought in different people to speak. I'd say that part lasted a couple hours? Then the student took us on a campus tour and we ate lunch. After lunch we had our interview and a group of professors came in and called out people's names. My interview was awful. The lady had a list of questions and read them one by one writing down my response. After everything I said she'd nod and say uh huh. Not dynamic at all. She asked me if I had any more questions probably 4 times in a row. At that point I was all out and it became very awkward! No really oddball questions were asked though! Don't let this scare you, because I heard from other people who loved their interviewer, so I must have just had a bad one! After the interview you could take an optional van ride to their clinic in downtown San Antonio. The day is very long so wear comfortable clothes and rest up!
