Mary Mercer, MD, MPH, is a Clinical Professor of Emergency Medicine at the University of California, San Francisco. She works clinically at Zuckerberg San Francisco General Hospital and Trauma Center and serves as Chief of the Medical Staff. She directs the Emergency Medical Services (EMS) and Disaster Medicine Section and serves as Associate Program Director for its fellowship, Medical Director of Alameda City Fire Department EMS, and Director for Well-Being for the UCSF Department of Emergency Medicine. Her work spans emergency and disaster medicine, public health, performance improvement, and organizational well-being. She has held leadership roles in San Francisco’s COVID-19 and mpox responses, including work on the city’s COVID-19 vaccination campaign.