Mary Mercer, MD, MPH is a professor of emergency medicine at the University of California San Francisco. She works clinically at Zuckerberg San Francisco General Hospital and Trauma Center (ZSFG), the only level-one trauma center in San Francisco and the acute care hospital of the San Francisco Department of Public Health (SFDPH). She serves in a number of roles at the intersections of Emergency and Disaster Medicine, Public Health, and Organizational Improvement and Culture.

Dr. Mercer currently serves as the Director of the Emergency Medical Services (EMS) and Disaster Medicine Section and Program Director for its Fellowship as well as the Medical Director of Alameda City Fire Department EMS. She additionally serves as the Director for Well-Being for the UCSF Department of Emergency Medicine, and is responsible for its well-being initiatives across all clinical sites and teams. She previously led ZSFG's Emergency Department Performance Improvement program and the hospital's Relationship Centered Communication program. Additionally, she has served in various strategic and operational leadership positions for the City and County of San Francisco and the San Francisco Department of Public Health for the COVID-19 and mpox responses, including leading San Francisco's successful COVID-19 vaccination campaign and partnerships.

Dr. Mercer has published extensively in the fields of EMS, Disaster Medicine, communication, and substance use disorder. She has served in leadership roles in state and national Emergency Medicine and EMS organizations and community boards of directors.

Dr. Mercer completed undergraduate training at Harvard University in the History of Science, followed by medical education at Columbia University College of Physicians and Surgeons. She completed Emergency Medicine residency at Stanford University and EMS/Disaster Medicine fellowship at UCSF/SFGH and received a masters in public health with a focus on Epidemiology at University of California Berkeley.