The Centers for Disease Control and Prevention--CDC--traces its roots to an organization established in the southeastern United States during World War II to prevent malaria among personnel training on U.S. military bases. On July 1, 1996, CDC formally celebrates its 50th anniversary as a federal agency dedicated to ensuring the public's health through close cooperation with state and local health departments and with other organizations committed to improving health in the United States and throughout the world. To commemorate this anniversary, this issue of MMWR presents reports that offer special perspectives: a historical overview of CDC; national morbidity data from June 8, 1946, and June 22, 1996; reprints of articles published in CDC...