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 goal is to help patients and families manage the acute illness that lead to hospitalization and transition to a healthy life outside the hospital environment.

I am passionate about effective management of acute medical issues while providing clear and concise medical information. In addition to clinical practice, I am interested in using technology innovations to improve patient health.

Outside of work, I am an avid SCUBA diver. 

My mission is to provide patient centered care that is both safe and effective.

Surgery can be a vulnerable time for patients. As an anesthesia provider, I find it rewarding to help people feel at ease prior to their procedures through listening and collaboration. Ultimately, no two anesthetics are the same, and having the opportunity to work with my patients to create a plan that tailors to their needs is what makes anesthesia so fulfilling. Outside of work, I enjoy running, gardening, cooking, and spending time with loved ones.