Since 2007, the Oklahoma Department of Corrections (ODOC) and the Oklahoma Department of Mental Health and Substance Abuse Services (ODMHSAS) have partnered to create a collaborative reentry process to improve the transition of incarcerated offenders with serious mental illness into appropriate community-based mental health services. ODMHSAS discharge managers are assigned to an office within the correctional facility that has special housing for intensive mental health services. The discharge managers serve as part of the ODOC institutional mental health treatment team that creates and implements the individualized treatment plans, including the reentry planning for offenders with a serious mental illness. Federal benefit planning is accomplished for eligible offenders, and the interagency collaboration has yielded a 90-percent Social Security approval rate. In-reach and aftercare services are provided by the Reentry Intensive Care Coordination Teams (RICCTs). The RICCT staff members meet with the offender at a minimum of 90 days before a projected release date and then work with the offender in the community until such time as the offender has adjusted to life following incarceration (usually up to a year post discharge). A vital component of the RICCT program is the inclusion of a Certified Peer Recovery Support Specialist on the team. These team members have firsthand, personal experience with mental illness and/or substance abuse and have been trained to offer peer support. In addition, out-stationed ODMHSAS specialists provide substance abuse treatment to those offenders in need during the reentry program. The program’s outcomes are very promising: service engagement, outpatient service utilization, and access to pharmacy services all increased and the recidivism rate for program participants decreased 41 percent from a comparison group. Collaboration between state and federal agencies in Oklahoma improves public safety and results in positive outcomes for participants.