In the United States and throughout the world, the majority of human immunodeficiency virus (HIV) infections are sexually transmitted. an estimated 12 million other sexually transmitted diseases occur annually in the United States. Avoiding sexual intercourse altogether or restricting sex to partners known to be uninfected will prevent infection; this needs to be promoted as the most effective strategy. Studies show that correct and consistent use of latex condoms is highly effective in preventing sexually transmitted HIV infection and other sexually transmitted diseases. The effectiveness of condoms depends on individual behavior leading to correct and consistent use. Further studies are needed to maximize the use and effectiveness of condoms for those who choose to be sexually active as well as to develop and evaluate other methods, particularly those more under the control of women. In the interim, our prevention message should be clear: When used correctly and consistently, condoms are highly effective; when used otherwise, they are not.