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.

In my career as an emergency physician, I have gotten to take care of patients in both the usual emergency department setting as well as some other unusual environment. Regardless of the location, one thing remains the same - it is about the patient and the care they need at a time of medical crisis. I spend most of my time outside of work, still engaged in medicine with a variety of emergency response organizations as well as the military.

My mission is to provide the very best clinical care to my patients- both in prenatal genetics and obstetrics. 

I grew up in a small town in Northern New York, and joined South Shore Hospital and Brigham and Women's Hospital in 2012. I completed my undergraduate and medical education as well as my general surgical training and surgical critical care fellowship at the University of Rochester in Rochester, NY. I am also fellowship trained in minimally invasive and bariatric surgery from Dartmouth Hitchcock Medical Center. I have had a long-standing passion in bariatric and weight-loss surgery and my goal in joining the South Shore Hospital team was to bring that expertise and opportunity to the South Shore community. The hospital has been very supportive in this endeavor and over the past few years we have created a collaborative team of providers from across institutions to start the South Shore Hospital Center for Metabolic and Bariatric Surgery. As medical director it has been my pleasure to help the program grow into a strong clinical component  of the department of surgery and create more outreach into the community. I am also actively engaged as a trauma surgeon and have a busy general surgery practice taking care of a variety of disease processes including the minimally invasive management of gallbladder disease, hernia, GERD, hiatal hernias, as well as the surgical management of a variety of other gastrointestinal disorders. When I am not working, I enjoy the simple things in life like relaxing by a large campfire or spending the day at the beach with my family. 

I believe in the prevention of disease and the promotion of healthy lifestyles for all children through education and dedication to quality care.

I like to treat each patient and family as individuals. I enjoy earning their trust and getting to know them as well as helping to navigate their child’s successes and challenges. I take pride in making sure we have full and open communication in our visits and your visit never feels rushed. My mission is to provide our patients with the best and most comprehensive pediatric care possible from birth until 21 years of age. I adhere to the “Golden Rule” in my life and practice which is the principle of treating others as one wants to be treated. Outside of work I enjoy exercising, horse back riding, and spending time with my family. I am an avid animal lover and we have many animals in our family.

I enjoy getting to know patients and treating the whole person. I focus on preventative care and supporting patients to reach their health goals.   

The doctor-patient relationship is at the center of your health care, and I strive to provide care that is collaborative and inclusive. I have a holistic approach, working with patients to treat the cause of medical problems, and reducing prescription medicines when it is safe to do so.   I am also pro-active, coordinating care and advocating for patients as they navigate the health care system. I enjoy caring for newborns, children, and family members of all ages, as well as helping with stress management and healthy lifestyle changes. 

When not working, I enjoy spending time with my family and my extra-large dog, reading, running, cooking, and playing flute, piano and guitar.  

I care for women throughout their lives—from adolescence through adulthood. I especially enjoy building long-term relationships and being with my patients through each step of their lives. From routine gynecological care to preconception, pregnancy, post-partum and menopause, I am here for my patient throughout her life. I chose OB/GYN as my specialty for the diversity of practice. It involves medical care, surgical care, and delivering babies. 

My parents inspired me—my father was a surgeon and my mother a nurse. I initially wanted to forge a different path and received my bachelor’s degree in Economics. I worked in financial public relations for a short while, but I kept coming back to what really interested me: medicine. I eventually went back to medical school to pursue my true passion. Outside of work, I love being outdoors—hiking, biking, boating, paddle boarding, and snowboarding. I also love to travel and spend time with my family and beloved dog and in quieter times enjoy reading and knitting.

It is an honor to have patients place their trust in my hands. I strive to provide excellent care throughout a patient’s entire hospital stay, be it in the ED, OR, ICU or ward. Outside of work I enjoy spending as much time as possible outside with my family and friends.

I provide comprehensive care to vascular patients. This ranges from the treatment of peripheral arterial disease, venous insufficiency and aneurysms, as well as hemo dialysis access.

I also have advanced wound care certification, as well as a board certification in Hyperbaric Oxygen Therapy.

It is a privilege to help people and establish long-term relationships with my patients. I believe that everyone's medical care should be individually tailored. We all have unique characteristics that need to be considered when deciding a treatment plan. Communication is paramount. 

I enjoy traveling to difference parts of the country and sampling unique cultures and cuisine. Having grown up in the Boston area, I enjoy watching sports with the local teams, and playing golf.