By increasing understanding of how excessive alcohol consumption and interventions to reduce excessive drinking can impact HIV-related health outcomes and sexual behavior that transmits HIV, this program project can contribute greatly to efforts to reduce alcohol use and improve the health of those living with HIV and to reduce the spread of HIV. Collaborative research in this domain has strong connections with Boston/Providence Center for AIDS Research where Prof Hogan serves as a co-Director of the Biostatistics Core and Brown Alcohol Research Center on HIV where Prof Liu serves as a co-Director of the Research Methods Core.