The criminal justice system (CJS) is disproportionately impacted by people with HIV and substance use disorders, such that one quarter of all HIV+ persons nationally cycle through the CJS annually. The CJS is therefore an important place to seek and empirically test interventions that address the Seek, Test, Treat and Retain (STTR) strategy to reduce community-wide HIV transmission. STTR requires that HIV is maximally suppressed, thereby resulting in decreased infectiousness. HIV+ prisoners maximally suppress HIV replication during incarceration. Unfortunately, viral suppression is lost within 3 months post-release, mostly as a consequence of relapse to opioids. Opioid dependence (OD) is present in 50% of all HIV+ prisoners nationally and 70-85% in the Northeast - OD is therefore a significant co-morbid condition requiring effective treatment. Opioid relapse is associated with decreased HAART adherence, discontinuation of HAART and increased HIV risk behaviors in the setting of viral replication - the perfect storm for HIV transmission. Effectively treating OD interrupts this relationship and has great potential to improve HIV outcomes and reduce community-wide transmission. Our team has confirmed for the first time that treating OD with buprenorphine (BPN) results in sustained viral suppression over the vulnerable 3-month post-release period. Adoption of methadone, despite its confirmed benefit, is minimal within the CJS due to philosophical, safety, regulatory and staffing concerns. BPN, a partial opioid agonist, is a more attractive option due to its safer profile and reduced regulation. Generic formulation now makes it affordable. Therefore, strategies examining the efficacy of BPN to improve adherence and retention in care, has great appeal to benefit the individual, but also to reduce HIV transmission within the community. Our specific aims are: 1) to conduct a placebo-controlled RCT of BPN for HIV+ prisoners with OD who are transitioning to the community and 2) to model the impact of BPN treatment on reducing HIV transmission. In the RCT, HIV treatment (HIV-1 RNA levels, CD4 count, ART adherence, retention in care), substance abuse (time to relapse to opioid use, % opioid negative urines, opioid craving), and HIV risk behaviors (sexual and drug-related risks) outcomes will be compared in 152 released prisoners and followed for 12 months. We bring together the strengths of seasoned researchers who have conducted research in the CJS for two decades in the areas of HIV treatment and adherence, Addiction Medicine and mathematical modeling. BPN, as a medication-assisted therapy, has great appeal within CJS due to lack of stigma, its documented safety in HIV+ patients, its unique pharmacology, lack of stringent regulation and its recently reduced cost. If this placebo-controlled trial of BPN among released HIV+ prisoners with OD demonstrates efficacy and safety, it is likely to become more widely adopted. As such, the individual, our health care system and society have a high likelihood to benefit - especially on reducing HIV transmission within the community.