At least 70 percent of prison inmates have drug problems needing treatment. Many drug treatment approaches have been developed, but the lack of program availability or limited enrollment has prevented many offenders from receiving treatment during incarceration. In addition, many jurisdictions have not kept pace with developments in both corrections and drug treatment. Offenders have diverse treatment needs; no one treatment approach is appropriate for all. Features of correctional programs that reduce recidivism include the appropriate intensity and duration of a program; its conceptual and theoretical basis; issues of program implementation, integrity, and quality control; and staff characteristics. Offenders with severe alcohol and drug problems require more intensive, diverse, and lengthy treatment than those with less serious problems. Offender drug treatment should include a range of both institutional and community-based interventions of various types, intensities, and durations. Behavioral and cognitive-behavioral treatment techniques have emerged as superior approaches for offenders. Motivational interviewing instead of confrontational techniques have promise for achieving problem recognition. Finally, research findings emphasize that community-based correctional programs are superior to those in institutions.