The factors associated with infection with the human immunodeficiency virus (HIV) in 216 homosexual men enrolled from November 1982 through December 1985, including 40 asymptomatic HIV seronegative, 20 asymptomatic seropositive, 66 with generalized lymphadenopathy (GLS), 37 with AIDS-related complex (ARC), and 53 with AIDS were studied. Because univariate analysis did not show significant differences between asymptomatic seropositive men and men with GLS or between men with ARC and AIDS, these groups were combined for analysis. In multivariate analysis the number of episodes of receptive and intercourse, the age at which regular sexual intercourse with a male partner was started, the use of enemas, sexual contact with someone with ARC or AIDS, and a history of hepatitis B were all independently associated with HIV infection. In univariate analysis the men with ARC or AIDS did not differ significantly from asymptomatic seronegative men as to number of episodes of receptive or insertive anal intercourse and number of sexual partners, but this most likely represents confounding that occurs when current risk factor behavior in fatally ill men is used in place of risk factor behavior at the time of HIV transmission. It indicates, however, that this group has become less sexually active and that HIV infection is largely spread by relatively healthy infected men.