Dr. Timmerman hails from the upper Midwest and maintained an active surgical practice in his home state of South Dakota for over 30 years. He completed his medical training at Washington University, St. Louis, MO, and surgical residency at Rush Presbyterian St. Luke’s Medical Center in Chicago, IL. He worked in private practice in his hometown of Watertown, SD, for nearly ten years before moving to Sioux Falls, SD to join Surgical Associates, Sanford Medical Center in 1998.

Dr. Timmerman also serves as Professor and Chair, Department of Surgery, USD Sanford School of Medicine for nearly a decade. Over the past 20+ years, he has served as this hospital’s past Level II trauma director, past Chief-of-Staff for Sanford Medical Center, surgeon physician lead, been on numerous hospital boards and committees, and, until just recently, the SD Governor appointed South Dakota State Trauma Director. With the assistance of Sanford Medical Center, USD Sanford Medical School and the American College of Surgeons (ACS), he helped lead the creation of a new general surgery residency program in South Dakota to train rural and community general surgeons.

Most recently, he was appointed to serve as the Executive Director of Undergraduate Medical Education for the entire Sanford Health Enterprise. He also serves on the South Dakota Board of Medical and Osteopathic Examiners. Dr. Timmerman volunteers extensively with the ACS, having presided as President of the South Dakota Chapter, Governor of both the South Dakota Chapter and the Association of Surgical Education, member and Chair of the Committee on Young Surgeons, Vice-Chair and Chair of the Board of Governors, and on the Advisory Council for Rural Surgery. He was recently Chair of the Health Policy and Advocacy Group (HPAG) and an active member of the ACS Board of Regents. In 2021, Dr. Timmerman was inducted as a Fellow into the ACS Academy of Master Surgeon Educators.