In earlier policy statements, this Report addressed the need to fully assess a person's substance abuse treatment requirements using standardized, validated instruments (Policy Statement 8, Development of an Intake Procedure), and the need for an individualized programming plan to respond to substance abuse and other issues raised during the intake process (Policy Statement 9, Development of the Transitional Plan). This policy statement goes into further detail about the substance abuse treatment aspects of that individualized programming plan. Because a history of using drugs and/or alcohol is common to so many people in prisons and jails-both generally and in connection with particular criminal offenses-it is especially key that addictions issues be addressed during the period of incarceration. Failing to capitalize on this opportunity to treat addiction poses risks to successful prisoner reintegration, public safety, and public health. Utilizing programs proven to be effective, prioritizing resources for those nearing release, and encouraging community-based aftercare will ensure better outcomes for re-entering prisoners and the communities to which they return.