Daniel M. Horn, MD is the Assistant Medical Director for Ambulatory Quality at the Massachusetts General Physician Organization, where he leads efforts to improve the quality of care for 160,000 patients across 21 primary care practices. Dr. Horn is also a primary care physician and Unit Chief at Internal Medicine Associates, where he provides comprehensive primary care and helps with day to day leadership of the largest primary care practices at Mass General. Dr. Horn is board certified in Internal Medicine and is an instructor at Harvard Medical School. He graduated Columbia University with a B.A. in Religion, and received his M.D. degree at SUNY Downstate College of Medicine. He completed his residency in primary care and population medicine at a joint program between Brigham and Women's Hospital, Harvard Vanguard Medical Associates, and the Department of Population Medicine at Harvard Medical School. Dr. Horn is trained in various process improvement methodologies and is certified as an Improvement Advisor by the Institute for Healthcare Improvement.