Dr. Horton is emeritus professor of medicine at Harvard Medical School and senior investigator at the Joslin Diabetes Center. He worked for 26 years at the University of Vermont College of Medicine where he served as director of Endocrinology and Metabolism, and then as chair of the Department of Medicine. In 1993, he was appointed professor of medicine at Harvard Medical School and medical director of the Joslin Diabetes Center. Subsequently he served as the director of the Clinical Research Center and a senior investigator at the Joslin Diabetes Center. Additionally, Dr. Horton was formerly director of endocrinology and metabolism at the New England Deaconess Hospital and chairman of the National Diabetes Advocacy Board.