Dr. Barker is a general internist who has spent his entire career as a physician and educator at the Johns Hopkins Bayview Medical Center (formerly Baltimore City Hospitals). In 1974, he founded and subsequently directed till 2012 the longitudinal practice for the residency program at Bayview. He was PI on HRSA training grants to establish the Johns Hopkins General Internal Medicine Program (1979-present) and the longitudinal Faculty Development Program for clinician educators (1988-present). He continues to teach in the faculty development program, which utilizes reflective practice as the chief learning mode. In 1995-1996, he received a Fulbright scholarship to introduce faculty development in the primary care system in Spain. Between the years 1982-2007 he co-edited the seven editions of the textbook "Principles of Ambulatory Medicine". Throughout his career Dr. Barker practiced as a general internist at Johns Hopkins Bayview.