Mark R. Dybul received his A.B. (1985) and M.D. (1992) from Georgetown University before completing his residency in internal medicine at the University of Chicago Hospitals (1995) and a fellowship in infectious diseases at the National Institute of Allergy and Infectious Diseases (1998). Dybul worked at the Department of Health and Human Services as the Assistant Director for Medical Affairs, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), as well as Co-Executive Secretary of the HHS HIV therapy guidelines for adults and adolescents. Dybul also holds the rank of assistant surgeon general and rear admiral in the U.S. Public Health Service Commissioned Corps, the uniformed service of HHS, and is a former member of the World Health Organization's Writing Committee to develop global HIV therapy guidelines. Before joining the OGAC, Dybul served on the Planning Task Force for PEPFAR, and led HHS in President Bush’s International Prevention of Mother and Child HIV Initiative. He worked in the positions of Assistant and Deputy U.S. Global Aids Coordinator before becoming Acting U.S. Global Aids Coordinator in 2006. Dybul took over the Office’s highest post after its first appointee resigned amid a prostitution scandal. Dybul himself resigned on January 22, 2009, the day after Hillary Clinton was confirmed as Secretary of State.