Objectives: Drawing upon existing meta-analytic reviews, this paper aims to systematically review the state of research on the effects of prison-based drug treatment programs on drug use and recidivism after imprisonment. Method: A systematic search was carried out through the Cochrane Library, the Campbell Collaboration Library of Systematic Reviews and Google scholar. Results: Based on the eligibility criteria set forth, three meta-analytic studies on the effects of prison-based drug treatment programs on drug use and recidivism were retrieved. All three meta-analyses consistently point to the positive effects of therapeutic communities both on drug use and recidivism. Findings regarding the positive effects of other incarceration-based drug treatment programs (e.g., counselling, narcotic maintenance programs, etc.) are less clear. Limitations as well as implications of the findings for research, policy and practice in Turkey are discussed.