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.

My treatment philosophy is to provide high quality, compassionate, and patient centered care.

Throughout my career at BU Medical Center and South Shore Health, I have divided my time between healthcare administration and direct patient care. Administratively, I have focused on medical education, patient safety and quality improvement. However, my true passion for medicine is driven by the bonds I build with my patients and caring for them throughout life. 

My philosophy is to provide quality evidence-based women’s healthcare in a setting that fosters mutual respect, shared decision-making and empathy.

At our office visit(s) I will focus on understanding your concerns and work with you to develop a diagnosis and management plan that is evidence-based yet tailored to your needs. You should expect to be treated with kindness, respect and privacy that everyone deserves.  I value your trust and understand that this must be earned.

My ideal day off would include spending time with my family, a good cup of coffee and mountain biking through the woods.  Sitting down for a few minutes to play the piano or guitar brings me joy.   We enjoy weekend trips to the Berkshires, NH and Maine for a change in scenery.

I strive to build a space where patients feel safe to discuss their health concerns and engage in shared decision-making.

Prior to joining South Shore Health, I had the privilege to train at UMass Family Medicine Residency and complete an additional year of fellowship to also care for patients living with HIV/viral hepatitis at the Family Health Center of Worcester.

Outside of work, I love spending time with my family, running, gardening, and camping/hiking.