Walter A. Orenstein, MD, DSc (Hon), is a Professor of Medicine, Epidemiology, Global Health, and Pediatrics at Emory University. From 2008 through 2011, he was Deputy Director for Immunization Programs at the Bill & Melinda Gates Foundation. From 1988-2004, he was the Director of the United States Immunization Program. He is a former Assistant Surgeon General of the USPHS.