The obstetric hospitalist and the obstetric and gynecologic hospitalist evolved in response to diverse forces in medicine, including the need for leadership on labor and delivery units, an increasing emphasis on quality and safety in obstetrics and gynecology, the changing demographics of the obstetric and gynecologic workforce, and rising liability costs. Current (although limited) research suggests that obstetric and obstetric and gynecologic hospitalists may improve the quality and safety of obstetric care, including lower cesarean delivery rates and higher vaginal birth after cesarean delivery rates as well as lower liability costs and fewer liability events. This research is currently hampered by the use of varied terminology. The leadership of the Society of Obstetric and Gynecologic Hospitalists proposes standardized definitions of an obstetric hospitalist, an obstetric and gynecologic hospitalist, and obstetric and gynecologic hospital medicine practices to standardize communication and facilitate program implementation and research. Clinical investigations regarding obstetric and gynecologic practices (including hospitalist practices) should define inpatient coverage arrangements using these standardized definitions to allow for fair conclusions and comparisons between practices.