One strategy to enhance supervision of preservice teacher trainees is on-site observation and feedback from another trainee, or peer coach. In this study, the effects of peer coaching were examined with five teacher trainees who were having difficulty learning the required instruction skills in their practica. Peer coaches provided immediatefeedback to trainees on teaching behaviors during reading instruction. They also summarized trainees' performance at the end of reading sessions. Effects of peer coaching were analyzed in a multiple baseline experimental design across trainees. Results indicated that effective teaching behaviors increased and ineffective teaching behaviors decreased with peer coaching for all five trainees. Also, effects generalized to math instruction. The potential uses of peers as coaches in preservice teacher education are discussed.