Initially, new residents share a period of "buddy call" with more senior residents for the first five weeks. After this orientation period, since there are five residents in each class, PGY-2 and PGY-3 residents are on call approximately every 10th night. Call is taken from home, but sleeping quarters are available at the Institute for use by residents for their convenience. PGY-4 residents are on call as surgical backup from home for a seven-day period every five weeks on average. Fatigue time is granted on an as-needed basis to all residents who require part or all of a post-call day off.