AbstractOver 250,000 endoscopic sinus surgeries are performed yearly in the United States alone. Although overall complication rates are low, errors can lead to significant morbidity due to the close proximity of the sinuses to the orbit and skull base and the resultant potential for blindness, cerebrospinal fluid leak, and catastrophic bleeding. Surgical checklists are endorsed by the World Health Organization and have been incorporated into most U.S. operating rooms as a measure to minimize avoidable errors. Standardized surgical checklists were developed with general and/or orthopedic procedures in mind, but in many instances they fail to incorporate concerns specific to endoscopic sinus surgery (ESS). In response to this clinical problem, we sought to develop and institute an ESS surgical checklist. This checklist can serve as a template for physicians who perform ESS and wish to prevent avoidable adverse events.