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 love caring for children and their families, whether it be supporting parents as they learn how to care for their newborns or helping a sick child recover from an acute illness. I believe in shared decision-making and incorporating each family's individual needs and goals into their child's care. Outside of work, I enjoy spending time with family, running, and traveling.

Patients with vascular disease often face many challenges—medical and otherwise. Consequently, I recognize that there are many important aspects to your care.  I also appreciate that having surgery is a major life event. With all of this in mind, I will do my best to provide you with patient-centered, high quality, effective and compassionate care.

Being a member of South Shore Health anesthesia department is personally and professionally rewarding. I believe having high standards of care allows for a safe and effective patient experience.

I received my undergraduate nursing degree from Boston College and my masters in anesthesia from Northeastern University. Practicing in the Boston area has been important to me as my children grow. We enjoy our friends and family as well as skiing, soccer and the outdoors.

I strive to provide high quality, safe, comprehensive anesthesia services and care to all my patients in the perioperative period. 

In the 8 years that I have been practicing anesthesia, I am resolute in my belief that creating and fostering a team environment with effective communication is crucial to developing an atmosphere of trust and the key to providing high quality care inside and outside of the OR with patients and colleagues alike.  As a collegiate athlete and previous marketing manager in my first career, I try to bring these skills and values into the OR and Anesthesia department. Outside of work, I love recreating in the outdoors. From snowboarding, hiking, biking, to waterskiing, beach lounging and lake time with my family, I love it all. Most importantly I love spending time with my husband and two daughters.