Special Projects of National Significance - Cooperative Agreements - A National Evaluation Model for Scaling HIV Care Engagement and Retention Strategies will serve as the Evaluation Provider for HRSA HAB’s 2026–2029 SPNS initiative, Strategies to Link, Engage, and Retain Men with HIV in Care. The project will conduct a rigorous, practical, multi-site implementation science evaluation of intervention strategies designed to link, engage, and retain men with HIV who are not consistently engaged in care or who experience serious barriers to staying in care. University of Missouri–Kansas City and the University of Missouri will work in close collaboration with HRSA HAB, the Implementation Technical Assistance Provider, implementation sites, an expert advisory board, and people with lived and professional expertise on this project. During pre-implementation, the team will support identification and selection of one or two evidence-based, evidence-informed, or emerging intervention strategies; assist with site selection and onboarding; review site implementation logic models; finalize common measures; establish IRB, data use, and data security procedures; and launch a secure REDCap-based data collection and reporting system. The evaluation will use a convergent mixed-methods design across eight Ryan White HIV/AIDS Program implementation sites. Guided by HRSA HAB’s implementation science approach and established frameworks including Proctor’s Implementation Outcomes Framework, EPIS, and CFIR, the evaluation will assess implementation strategies, implementation processes, intervention adaptations, barriers and facilitators, and outcomes including adoption, acceptability, appropriateness, feasibility, fidelity, reach, cost, and sustainability. The project will also assess client and service outcomes, including linkage to care, engagement in care, retention in HIV medical care, appointment and referral completion, viral suppression, and related HRSA HAB performance measures. We will provide ongoing evaluation-specific technical assistance to sites, including training on REDCap, data collection, clinical outcome abstraction, process tracking, confidentiality, IRB requirements, data use agreements, cost reporting, and dissemination. Routine data quality monitoring, monthly site reports, site visits, monitoring and technical assistance calls, and learning sessions will support rapid-cycle feedback and continuous improvement. Cost analyses will estimate the resources required to implement and sustain selected interventions across diverse Ryan White settings to impact HRSA HAB performance measures. Findings will be rapidly shared with HRSA HAB, the ITAP, implementation sites, and the broader Ryan White community through monthly reports, biannual presentations, learning sessions, briefs, conference abstracts, manuscripts, and user-friendly implementation materials. The project will generate actionable evidence about what works, for whom, under what conditions, and at what cost, supporting replication, adaptation, scale-up, and sustainability of effective strategies to improve long-term HIV care engagement, viral suppression, and outcomes among men with HIV.