PROJECT SUMMARY/ABSTRACT IPV is a pervasive and serious public health issue, affecting nearly one in three women nationally in their lifetime. IPV-exposed women have rates of drug and alcohol misuse that are 2–7 times higher than women nationally. As many as 70% are tobacco smokers. [IPV-exposed women have sex with more risky partners, including those who are HIV-positive, IV drug users, and nonmomgomous, and are more likely to engage in unprotected sex and trade sex, and report more sex partners.] PTSD is highly prevalent among IPV-exposed women (31 to 84%), and IPV-related PTSD symptoms are positively associated with drug, alcohol, and tobacco use and HIV/sexual risk. Despite the clear clinical relevance of PTSD in this population, particularly with regard to substance use and risky sex, no studies have explicated mechanisms that may account for relations between PTSD symptoms and substance use and HIV/sexual risk behaviors among IPV-exposed women. Emotion dysfunction has been identified as a key mechanism in the pathogenesis of a wide range of psychological difficulties and maladaptive behaviors, including PTSD, substance use, and HIV/sexual risk. Yet, research on mechanisms underlying these health outcomes generally, and the potential mechanism of emotion dysfunction in particular, is absent in this population. IPV-exposed women constitute a unique population distinct from other trauma-exposed populations. IPV is chronic; women are recurrently victimized by their partners and repeatedly exposed to potentially traumatic stimuli in their environment. This unique context poses increased risk for PTSD symptoms, emotion dysfunction, substance use, and HIV/sexual risk. Existing intervention models for treating PTSD and co-occurring substance use and/or risky sex (e.g., Seeking Safety, Project Connect) were not developed for women who remain in unsafe situations, are seldom community-based, and do not have an integrated focus on IPV, PTSD, substance use, and HIV/sexual risk. Consistent with current initiatives (e.g., NIH strategic plans), identifying mechanistic processes, across multiple systems (i.e., physiological and behavioral), underlying the relations among PTSD, substance use, and HIV/sexual risk in this population is a critical first step in developing targeted interventions that are safe for IPV-exposed women in the community. The proposed study addresses such critical gaps in the research with an innovative, context-specific, multi-method approach among 150 women currently experiencing IPV and using substances. Findings will [identify relations among physical, sexual, and psychological IPV and emotion dysfunction;] explicate the role of emotion dysfunction in PTSD symptoms and risk-taking propensity in the lab and substance use and HIV/sexual risk in the real-world; and test the convergent validity of lab and real-world data. The role of emotion dysfunction in PTSD symptoms and risk-taking propensity will be measured in the lab via a no...