Today, Rochelle P. Walensky, MD, MPH, officially begins her post as the 19th director of the Centers for Disease Control and Prevention (CDC) and the ninth administrator of the Agency for Toxic Substances and Disease Registry (ATSDR). U.S. President Joe Biden selected Dr. Walensky to lead the agency in December. Dr. Walensky comes to CDC from Massachusetts General Hospital, where she served as Chief of the Division of Infectious Diseases from 2017-2020; and Harvard Medical School, where she served as Professor of Medicine from 2012-2020. Additional biographical information is available on the CDC website.