Project Summary/Abstract We will conduct innovative, mixed-methods life course research on interpersonal victimization, protective processes, and mental health and substance use among young transgender women. Young transgender women experience disproportionately high rates of interpersonal victimization, including child abuse, intimate partner violence and sexual assault, as well as transgender-related community violence. Although evidence indicates that cumulative victimization increases the likelihood of poor mental health in cisgender women, these patterns are under-explored with young transgender women. The proposed study will address these gaps by conducting a two-phase mixed-methods study with young transgender women in Chicago, IL and Milwaukee, WI. In Phase I, we will use the life history calendar (LHC), an innovative methodology for collecting life course data, to examine comprehensive experiences of interpersonal victimization in a sample of N=120 trans women aged 18-35. The LHC uses a large grid and landmark events to cue retrieval of events from memory. These events can then be quantitatively identified to determine the number, timing, and forms of victimization. Participants will also complete a brief survey assessing mental health outcomes and help-seeking and protective processes. In Phase II, we will conduct in-depth interviews with a subsample of n=30 trans women purposively selected from Phase I to deepen understanding of novel protective processes and help seeking barriers/facilitators. The specific aims are to: 1) Identify trajectories of interpersonal victimization, help-seeking, protective processes, transition-related milestones, and mental health outcomes across the life course in a sample of N=120 young trans women ages 18-35 in Chicago and Milwaukee. We will use the LHC to structure interviews to quantitatively capture life events, e.g., interpersonal victimization, help-seeking, protective processes, mental health outcomes, including suicide attempts and substance use, and transition-related milestones. Multilevel and mixture modeling will be used to identify trajectories of these life events across time; 2) Identify how different trajectories of interpersonal victimization influence current mental health outcomes, including PTSD, depression, anxiety, suicidal ideation, and substance use, and examine how protective processes (e.g., social support, self-esteem, and community resilience) moderate the effects of violence on mental health outcomes. Using LHC and survey data, we will use growth mixture modeling to examine direct and moderated relationships over the life course; and 3) Explore patterns of formal and informal help-seeking behaviors, barriers to seeking help, mental health care needs, and protective processes through qualitative life history interviews with n=30 young trans women. Women with different trajectories of interpersonal violence will be purposively sampled and interviewed to obtain nuanced and in-dep...