Medication-assisted treatment (MAT) is the use of FDA-approved medications with behavioral therapies to treat alcohol and opioid use disorders.  When provided as part of the rehabilitation and reentry process for people incarcerated in correctional facilities, MAT addresses substance use as a criminogenic risk factor and may contribute to long-term recovery and reduced recidivism. As with any medication or treatment, there is risk of diversion; but, with the appropriate program elements in place, sheriffs, wardens, and jail administrators can provide this effective and evidence-based treatment to individuals during incarceration.  This action brief addresses strategies and techniques to decrease the diversion of drugs used in MAT.