William Tollefsen, MD is the EMS and MIH Medical Director for South Shore Health. Dual-boarded in Emergency Medicine and EMS Medicine, Dr. Tollefsen works clinically as an Emergency Physician at South Shore Health in addition to his role as EMS Medical Director.

One of few physicians in the country to receive the prestigious "FAEMS" recognition, Dr. Tollefsen is also the Medical Director for OEMS Region IV, serving 61 cities and towns of the Metro-Boston EMS Council. As the current EMS Medical Director for eight municipal and three private ambulance services on the South Shore, Dr. Tollefsen interacts and provides oversight for over 400 Paramedics.

Dr. Tollefsen graduated from New York Medical College and completed residency training in Emergency Medicine at Harvard University, Brigham and Women's, and Massachusetts General Hospital. He completed a fellowship in Emergency Medical Services and Critical Care Transport at the University of Massachusetts, where he worked as an Emergency Physician and Flight Physician for UMASS LifeFlight. He completed an MBA at the Isenberg School of Management at UMASS Amherst, and holds a Master of Medical Science degree from the Boston University School of Medicine.

A former pre-hospital provider, he is actively involved in EMS system design, paramedic education and Critical Care Transport Systems. He works closely with multiple EMS, Fire and Law Enforcement agencies throughout Massachusetts.

His research interests include systems of care, resuscitation, airway management, and paramedic education.

I started practicing primary care at Boston Medical Center in 2001 and was part of the Faculty of Boston University's School of Medicine. In 2010, I transitioned to the Quincy and Braintree area to continue serving as a primary care physician and urgent care provider. I graduated from the University of Puerto Rico School of Medicine and completed my residency in Internal Medicine at the Hospital of Saint Raphael/Yale-New Haven Hospital.

My focus is to provide high quality health care and excellent communication with my patients. 

I have worked clinically as a PA since 2014 in a variety of health care settings including hospitals, clinics, and subacute rehabs. This has provided me a deeper understanding of the healthcare system and the trajectory of the patient experience across multiple healthcare settings. Outside of work, I love music, traveling, and food.