The purpose of this K24 renewal is to continue to exponentially enhance Dr. Carla Kmett Danielson's mentorship and research program in innovative approaches to risk reduction of HIV acquisition and addiction among adolescents, with a particular focus on trauma-exposed populations. Over the prior K24 funding period, Dr. Danielson, a clinical psychologist and scientist, demonstrated she is the ideal candidate for this mechanism. The impact of her protected time for expanded research and mentorship are evident through numerous achievements from over this funding period, including productive mentorship of 23 mentees (>50% from underrepresented backgrounds), awards in recognition of this mentorship, a new line of research in mHealth HIV and addiction prevention intervention, and continuous federal-funding of her innovative patient oriented research (POR) in which she has involved her mentees. Her mentees, who have included early-career faculty, post-doctoral fellows, and predoctoral psychology interns, are making significant contributions to the HIV prevention, substance abuse, and traumatic stress fields through high-impact publications and new lines of NIH-funded research. The proposed K24 award renewal will be essential for providing the time and resources necessary for the candidate to expand her research skills in virtual reality technologies for young people at high risk for HIV acquisition and addiction, sustain her mentoring program and capacity, and further stimulate the research program of her mentees (e.g., through a trainee pilot award program that was successful during the prior funding period). Innovative research proposed by Dr. Danielson under the K24 renewal involves refinement and evaluation of a virtual reality clinical tool to improve trauma-informed assessment and prevention of substance use and sexual risk behavior with at-risk young people. This will be accomplished through input and training from leading experts in the virtual reality-high risk behavior research field; an internationally known technology firm in virtual reality tool development (Virtually Better, Inc.); qualitative research; an Advisory Board of consumers and experts; and evaluation of the validity, acceptability, and feasibility of the refined virtual reality tool with high risk populations (e.g., adolescents in treatment for substance use problems and traumatic stress; young adults presenting to a high-risk HIV clinic) and health care providers. Dr. Danielson's proposed mentorship activities, current federally- funded research projects, and aims to pursue innovative, virtual reality research in the areas of HIV prevention, substance use risk reduction, and trauma among adolescents harmonize well with NIDA priorities that call for research designed to evaluate the application of new technologies for delivering adapted prevention interventions targeting substance use and prevention of HIV acquisition. The proposed research affords rich training opportunities fo...