The scientific burden of proof for new therapies and technologies in obstetrics and gynecology has risen steadily over the past 15 to 20 years, and the randomized clinical trial has become integral to this higher standard. Data monitoring and safety committees are now critical components of clinical trials, yet their history, rationale, methods of operation, and overall role have not been well-characterized in the obstetrics and gynecology literature. In this review, an overview of the important and evolving role of data monitoring and safety committees is provided.