Published in Annals of Internal Medicine, the following systematic review examines the effects of shift length, protected sleep time, and night float on patient care, resident health, and education outcomes among residents. The review finds that a majority of studies find shorter shifts are associated with decreased medical errors, motor vehicle crashes, and per-cutaneous injuries. Only 2 studies assessed protected sleep time and reported that residents’ adherence to naps was poor. Night floats described in 33 studies involved 5 to 7 consecutive nights. Overall, specific recommendations about shift length, protected sleep time, and night float should acknowledge the limitations of this evidence.