As the Medical Director of Addiction Medicine at South Shore Health, I work to tackle the defining medical challenge of our time: Substance use and alcohol use disorder.

In addition to seeing adult patients at South Shore Hospital, I work with colleagues across South Shore Health to develop and implement a comprehensive addiction medicine treatment program. This program will connect patients with the resources they need to manage substance use disorder, no matter if they come to us through the Emergency Department, primary care, or another setting. Additionally, I serve as Medical Director for Spectrum Health System's opioid treatment program, ATS/detox, CSS, and therapeutic community in Weymouth.

Prior to my work at South Shore Health, I helped launch the Bridge Clinic at Boston Medical Center, which connected patients with treatment options for substance use disorder. I also served as Medical Director for Spectrum Health Systems’ Opioid Treatment Program in Weymouth.

In my spare time, I enjoy baseball, reading fiction, snowboarding, and cooking.

Being a physician is an honor and a privilege I have enjoyed since graduating from The Johns Hopkins University School of Medicine in 1979.  As my patients know I am interested in your life, your passions and the Orthopaedic issues that frustrate you and how I might be of assistance to you.  Surgery is not always a solution.

I take care of newborn infants and their great grandmothers.  In an era of sub-specialization, I am the "silver haired" General Orthopaedist but have maintained my surgical skills and remain confident in my abilities.  I have been fortunate to have treated multiple generations of my friends and neighbors here on the South Shore and work in a hospital committed to clinical excellence and compassionate care.

My journey to becoming a physician has led me not only to multiple states, but also abroad to Haiti and Jordan on medical mission trips. I am continually learning from my patients and their experiences. I translate this clinical knowledge to all of my new patients. 

Outside of work I enjoy exercising, traveling, and spending time with my family

As a primary care clinician, I have the opportunity to develop a trusting partnership with my patients and their families to help them live a healthy lifestyle. I enjoy diagnosing and treating the various illnesses that affect patients during their lifetime, and take great pleasure in seeing them recover. It is important for me to listen carefully to my patients' concerns so we can work together to meet their individual healthcare needs.  

In my free time, I enjoy swimming, running, cycling, and skiing, in addition to spending time with my husband, adult children, and our new granddaughter.

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.

As a medical student, I was unsure what my clinical focus would be. Once I saw my first delivery, it was clear that this was my future. I started my internship and residency training here in Boston. After moving to California and spending several years practicing there, I knew I wanted to return to Massachusetts. I have been at South Shore Hospital for nearly ten years now and am grateful to work with the women of the South Shore. After many years practicing both Obstetrics and Gynecology, I realized my true love was the Birthing Unit and transitioned to a Laborist position. I am privileged every day to be part of something so amazing and love that I get to share in such an important family experience.

My treatment philosophy and ultimate goal is to collaborate with families to achieve the best birth experience while helping to ensure the wellbeing of mom and baby.

My goal is to establish open communication with patients so we can work together on taking ownership of their health and wellness.

I enjoy the meaningful relationships I have built and the inspiration I draw from patients every day in clinic. A healthy dialogue is an important part of the provider-patient relationship. Outside of work, I enjoy spending time with my family, writing, and staying active outdoors.

It has been my privilege to practice medicine and to have made a difference in the lives of my patients over the past 21 years. I enjoy the challenges of practicing internal medicine in a hospital setting and working as part of a team with our excellent hospitalist providers, consultants, nursing and ancillary staff. I served as Medical Director of the Hospitalist Department from 2009-2015 and am proud to say that we have an amazing program with dedicated clinicians who genuinely enjoy the care of hospitalized patients and are committed to excellence in their every day work. I enjoy giving back by participating in the Pan Mass Challenge which raises critical funds for cancer research and the Multiple Sclerosis cycling events. I enjoy boating, hiking and camping, and long distance bicycling and, most importantly, spending time with my family.