Opioid use disorder (OUD) in US jail populations is a major public health concern. Individuals with OUD who do not receive treatment during incarceration have high rates of relapse and are exposed to increased risk of overdose death upon release. Despite the proven effectiveness of methadone and extended release naltrexone treatment for OUD, these medications are rarely initiated prior to release from jail. The National Institute on Drug Abuse funded a cooperative study consisting of three randomized clinical trials to examine the effectiveness of pharmacotherapy initiated prior to release from jails in Albuquerque, NM, Baltimore, MD, and New York, NY. These studies randomly assigned opioid-addicted adults in jail to begin: methadone treatment with or without patient navigation, or an enhanced treatment as usual condition (in Baltimore, N=225); to extended release naltrexone with and without patient navigation, or enhanced treatment as usual (in Albuquerque, N=150); and, to extended release naltrexone or enhanced treatment as usual (in New York, N=255). This series of presentations will outline the scope of the opioid addiction problem in jails, the rationale and use of these medications in jails, challenges in implementing these approaches in jail and post-release, and medical and psychiatric co-morbidities in this patient population. Main results to date will be presented, including: patient willingness to be treated, rates of study treatment retention after release, and community drug treatment outcomes. Audience discussion surrounding opioid treatment in criminal justice settings will be encouraged.