CLARE|MATRIX (C|M) and its partners will build on its past success as a grantee of SAMHSA Targeted Capacity Expansion: HIV funding to serve a catchment area of more than 1Million individuals in California's South and Central Los Angeles area. The population of focus for this project will be predominantly African American and Latinx adults with opioid use disorder (OUD) who are injection drug users residing in Los Angeles County (LAC) at risk for HIV/AIDS and viral Hepatitis. C|M's MAI project will expand access to MAT for OUD and screening for HIV and viral Hepatitis using an In-House Implementation model for OUD services. Treatment services for HIV and viral Hepatitis will be referral-based and facilitated through MOAs. With this blended approach, C|M and its partners will impact the disparate rates of injection drug use and HIV/hepatitis infection rates in LAC, an EHE priority jurisdiction. By the end of the project, 430 people will receive treatment that will reduce drug use, drug injecting, and the practice of risky behaviors. These services will be enhanced with additional services that increase participant awareness of HIV and viral Hepatitis status, access to treatment, and access to antiretroviral therapy (ART) and other medical care. Care for co-occurring mental health disorders will be provided via specialty care and case management. C|M will also impact community rates of overdose and infectious disease related to injection drug use through 260 harm reduction engagements, 120 health and wellness groups, and 200 community education and awareness events. These goals will be accomplished by a team of 3.15 clinical, program, and contracted staff. A project director will ensure successful implementation, and an evaluator will provide regular reports to ensure all quality and access goals are met.