Initial phone interview with HR, to weed out who they will bring in. Once the face to face is set up the interview is with 4-6 managers and someone who will be a co-worker (one at a time, not as a group) in the group you're hiring into. Each lasts 45 min to an hour and will cover both a technical review as well as an evaluation of personality to determine how well the potential employee will fit in with everyone.