I grew up in southern Maine and attended Harvard University for my undergraduate education. While at Tufts University School of Medicine and Mount Auburn Hospital in Cambridge, my focus was on primary care medicine. I believe in the dignity of each of my patients. Respect, compassion, and reliability are among my goals in patient care. In my free time, I enjoy the outdoors and the arts, usually in the company of my family. 

I have been a physician's assistant in women’s health for close to 30 years on the South Shore. I enjoy seeing women in their many phases of life. I feel privileged when patients I met at the start of my career bring their daughters and granddaughters in to see me for their care. When not working, I enjoy spending time with my family.

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.