Abstract
Recent years have seen a revivification of correctional treatment. Meta-analysis has played an important role in this trend. However, the discussion on these results has been just as controversial as the reviews on the “nothing works” debate 20 years ago. This controversy is due to a mixing up of facts and values. The present paper should contribute to the consensus on facts. First, it reports on an update of a meta-analysis on the treatment of adult offenders in German social-therapeutic prisons. This is followed by an overview of North American meta-analyses that have concentrated mostly on programs with juveniles. The outcomes show fairly consistent but low overall effects. Most meta-analyses also tend to agree on differential effects (e.g., modes of treatment, design characteristics, settings). Nonetheless, there are still major deficits in evaluation research. Finally, future perspectives of the revived discussion on offender rehabilitation are discussed.