Abstract Title* Rare and Preventable: A Qualitative Study of Diversion of Medication for Opioid Use Disorder in Jail Presentation Track* Please indicate all tracks that best describe your poster. Examples of each track are provided but are not intended to be exhaustive. Treatment Development and Evaluation (e.g. development and testing of an intervention, evaluating community programs) Other (please describe below) Other Presentation Track(s) If none of the presentation tracks above apply, please specify track(s) below. Qualitative Data Analysis using an Inductive Approach Abstract*(Up to 325 Words) Abstracts must represent the work of authors listed. Abstracts are limited to 300 words total, not including the title. Abstracts should include the following sections: • Background/Objectives • Methods • Results • Conclusion. All information should be reviewed prior to submission to ensure completeness. Please note that we ask for author information at the end of the submission form. Abstract Background: Correctional officials often cite diversion of medication to treat opioid use disorder (MOUD) (e.g., buprenorphine) as a reason for not offering MOUD treatment in jails and prisons, but it is poorly understood whether these fears are justified. Objectives: We aimed to understand staff perceptions of medication diversion from jail-based MOUD programs and the factors that contribute to and prevent diversion. Methods: We conducted semi-structured in-depth interviews and focus groups in 2019-20 with 61 administrative, security, behavioral health, and clinical staff who implement MOUD programming in seven Massachusetts jails. We conducted qualitative data analysis in Dedoose using an inductive approach. Results: Contrary to staff expectations, buprenorphine and methadone diversion occurred infrequently after MOUD program implementation. The MOUD program changed staff views of buprenorphine, i.e., as legitimate treatment instead of as illicit contraband. Also, the program was perceived to have disrupted the illicit buprenorphine market in jail and reduced related violence. Proactive strategies were essential to prevent and respond to buprenorphine diversion. Key components of diversion prevention strategies included: staff who distinguished among different reasons for diversion; comprehensive and routinized but flexible dosing protocols; communication, education, and monitoring; patient involvement in assessing reasons for diversion; and written policies to adjudicate diversion consequences. Conclusion: With appropriate protocols, buprenorphine diversion within correctional MOUD programs is rare and preventable. Best practices in program design help limit medication diversion and inform correctional officials and lawmakers as they consider whether and how to provide MOUD treatment in correctional settings. Disclaimers/Funding Please add any disclaimers, conflicts of interest, or funding statements here; this information will not count against the abstract word limit. Financial support: The National Institute on Drug Abuse (NIDA) 3UG3DA044830-02S1 and 1UG1DA050067-01 Conflicts of interest: The authors report no conflicts of interest.