Policy Research, Inc. (PRI), in collaboration with its partners, will operate SAMHSA's Homeless and Housing Resource Center (HHRC). Through innovative and responsive training and technical assistance (TTA), PRI will expand the availability of high-quality virtual and in-person trainings in evidence-based housing and treatment models for adults, children, and families who are experiencing or at risk of homelessness and have SMI, SED, SUD, or COD. Individuals experiencing homelessness, particularly youth and women, have disproportionately high rates of lifetime exposure to trauma, adverse childhood experiences, and victimization which are strongly tied to SMI/SED, SUD, and COD. Opioid use disorder (OUD) and opioid overdose is disproportionately high among people experiencing homelessness, and Veterans experiencing homelessness have high rates of SMI, SUD, and suicidal ideation. Lack of transportation and limited availability of treatment resources and services are common barriers to accessing care. However, street outreach/medicine, peer navigation, medication-assisted treatment, and case management have proven to be effective in increasing health care utilization and reducing health disparities. To address barriers to care and increase access to treatment and housing, PRI developed five overarching goals for HHRC: increase knowledge about treatment and recovery services, increase knowledge about accessing and retaining housing, increase the number of individuals assisted into housing as a result of HHRC trainings, deliver TTA to PATH providers to ensure fidelity to program implementation and HMIS data standards, and develop a systematic process to ensure that all HHRC resources incorporate current EBPs and address emerging issues. Successful training completions across all SAMHSA regions, participant feedback about the utility of the training in their work, and reported increases in housing access will indicate program reach and effectiveness. Over the course of five years, PRI and its partners will develop and launch 10 online courses, and facilitate 25 webinars, 8 Learning Communities, 10 in-person Summits, and 60 State PATH Contact Network calls. Trainings will be targeted to health professionals, housing and treatment service providers, and members of the public.To further ensure the relevancy and effectiveness of the various learning mechanisms applied in this work, an Expert Panel will meet quarterly to discuss emerging needs, evidence-based solutions, new topic areas to address, and HHRC training impact. We propose reaching approximately 2,000 individuals in the first year through 5 webinars, 12 PATH calls, 2 HHRC Summits, and on-call PATH and HMIS TA; however, our reach will increase exponentially with the launch of two online courses by the end of Year 1 and the introduction of specialized PATH/HMIS Learning Communities in Year 2. We estimate reaching approximately 23,000 people over the lifetime of the grant through a combination of virtual and in-person trainings and on-call TA. Additionally, the development of 15 toolkits with EBP implementation guidance will further expand the efficacy of our TTA. All services offered will be publicly available, free of charge.