About the Editors Richard A. Kaslow, M.D., M.P.H., is Chief of the Epidemiology and Biometry branch, Microbiology and Infectious Diseases Program, at the National Institute of Allergy and Infectious Diseases, National Institutes of Health, in Bethesda, Maryland. Donald P. Francis, M.D., D.Sc., is the Centers for Disease Control AIDS Adviser at The State of California Department of Health Services in Berkeley, California.