PROJECT SUMMARY/ABSTRACT - Implementation Science and Health Systems (IS/HS) Core The Implementation Science and Health Systems (IS/HS) Core advances the scientific mission of CAPS by equipping scientists with the skills and expertise to conduct research that brings proven-effective interventions to scale in diverse settings. HIV intervention science now includes a robust toolkit, including biomedical approaches for primary and secondary prevention, effective behavioral strategies, and interventions to address social-structural barriers to prevention and care. Unfortunately, many efficacious interventions have not yet attained their full potential, owing to challenges in meeting the complex needs of vulnerable communities who experience intersecting and co-occurring health and social conditions and to inadequate integration of interventions into routine practice across health delivery settings and systems. The IS/HS Core will build capacity within the Center for AIDS Prevention Studies in applying implementation frameworks, designs, and strategies to integrate interventions and services into both traditional and nontraditional settings to ensure service access for the populations most in need. The Core reflects our belief that achieving optimal and equitable delivery of HIV services requires research skills that draw on implementation and dissemination theories, fluency in working within diverse health systems, and a commitment to address intersecting and co-occurring health and social conditions. To do so, the IS/HS Core takes an ecological and systems-level lens, focusing on the context of the populations served, health care delivery settings, and stakeholders who can shape responses. Our work will be guided by three aims: (1) to stimulate rigorous research to optimize intervention implementation through a focus on implementation theory and intervention implementation strategies, adaptation, and refinement; (2) to promote expertise in integrating interventions within diverse health delivery settings through work to support program integration, measurement, and data integration; and (3) to build capacity to sustain interventions in diverse contexts via support for studying policy contexts, partnerships outside of health settings, and promoting team science. The IS/HS Core will promote CAPS' objectives and the Core aims through seminars, peer review, consultations, referrals, and town halls addressing critical research topics. To this foundational mix of offerings, the Core will add novel approaches, including skills-building workshops, multidisciplinary symposia, conferences, and growing a multidisciplinary network of collaborators across UCSF, health systems, and community agencies.