We build in this proposal on ongoing work in AIDS prevention among minority homeless mentally ill men and women in New York City. In our work with homeless mentally ill men, we are presently studying the determinants of HIV risk behaviors among psychiatric patients in the Fort Washington shelter for men in New York City. These men have the highest reported prevalence of HIV infection of any mentally ill population which has been assessed. We seek funding to proceed with the development and testing of an intervention for them. The goal of the intervention will be to reduce the frequency of unprotected sex. We will adapt intervention methods for a population that is mainly African-American and Latino, chronically ill, socially disadvantaged, and often afflicted by cognitive impairments that impede social learning. thus, the intervention will be highly focused on one or two outcomes, use skills training methods that have proven effective in schizophrenia, target critical barriers to behavior change in this population, take account of the patterns of sexual relationships among these patients, and address the relations between psychiatric symptoms and risky sexual behaviors. It will also be culturally appropriate. We will test the efficacy of the intervention in a randomized clinical trial. In previous work we have established our ability to complete a randomized clinical trial with follow-up in this population. The study will include 125 experimental and 125 control subjects. Participants will be assessed on a monthly basis for twelve months after the experimental and control treatments. In our work with homeless mentally ill women, we are at an earlier stage. The present proposal includes funding for elicitation and the development of a feasible intervention for them. It is intended that supplementary funds will be sought in due course for testing and application of the intervention for women.