In both the USA and abroad, HIV incidence is resurgent among MSM, while HIV prevention for MSM has faltered. Research is urgently needed that holds high potential to re-engage MSM in prevention by taking HIV prevention in genuinely new directions. Through our online HIV prevention research on Men who use the Internet to seek Sex with Men (MISM), our preliminary studies show MISM to be high consumers of Sexually Explicit Media (SEM), particularly Internet-mediated SEM. Yet few studies of gay SEM exist. None have examined a potential link between SEM consumption, genre of SEM (depicting bareback or safer sex) and HIV risk behavior, and none appear to have assessed ways of using SEM to reinforce safer sex. Grounded in sexual script theory, our long-term objective is to study, develop and test ways of using SEM to lower HIV risk behavior among MISM. We have identified 3 priorities: a) to study exposure to and consumption of SEM by MISM;b) to investigate an hypothesized relationship between SEM consumption and HIV risk behavior which we hypothesize is moderated by SEM genre;and c) to conduct a needs assessment to identify how SEM could be better used to promote HIV prevention and sustain low risk behavior. To achieve these aims, first we will conduct a qualitative study using 16 focus groups of gay SEM consumers to identify both normal and problematic use of SEM, and to examine the effects of safer sex SEM versus bareback SEM. Then we propose to adapt published scales on the effects of heterosexual SEM to measure gay SEM and to develop new measures specific to this study. The psychometric properties of these measures will be tested using a repeated measures online test-retest reliability study of 120 MISM. Usability laboratory and user testing will be conducted to optimize online delivery across platforms. Finally, we will conduct a cross-sectional online survey of SEM use in 2000 MISM conducted nationally with intentional over-sampling of MISM of Color, HIV+MISM, MISM engaging in UAI with multiple partners, and low SEM-using MISM. PUBLIC HEALTH RELEVANCE: The primary significance to public health lies in its potential to assess what relationship, if any, exists between SEM consumption and HIV risk, and to advance a potential new area of HIV prevention for MISM based on strengthening safer sex depictions in SEM. Significance to science includes the development of several new scales and methods to study Internet SEM among MISM, and data to inform a neglected area of study. Significance to industry includes a needs assessment that can be used to inform the development of future SEM. We believe the first study of the relationship between gay SEM consumption and HIV risk is, by definition, highly innovative. Further, given our team's current research in developing online interventions, we believe we are the right team in a superb environment both to conduct this formative research and to use its findings in future intervention development.