This paper introduces the problem of scheduling emergency room physicians. We interviewed physicians from six hospitals in the greater Montreal, Canada area, in order to understand the emergency room scheduling problem. Extracting the real scheduling problem is difficult because physician working conditions are based on informal mutual cooperation which is usually not documented. We present the characteristics of the scheduling problem and the scheduling techniques currently used in the six emergency rooms we analyzed. Using the scheduling problems of Charles-Lemoyne Hospital and the Jewish General Hospital, we show how to modify a hospital's existing scheduling rules to develop techniques which produce better schedules and reduce the time needed to build them.