Consistent with previous meta-analyzes the sexual and general recidivism rates for the treated sexual offenders were lower than the rates observed for the comparison groups. Programs that adhered to the risk-need-responsitvity (RNR) principles showed the largest reductions in sexual and general recidivism. It was believed that the RNR principles should be a major consideration in the design and implementation of treatment programs for sexual offenders. The effectiveness of treatment for sexual offenders remains controversial, with the debate in the scientific literature remaining divided. In this meta-analysis, 23 recidivism outcome studies were examined on whether the principles of effective interventions for general offenders also applied to psychological treatment of sexual offenders. The study also examined the extent to which the study results varied based on study design and the influence of the age of the sample and the possible effects of community- versus institutional-based treatment. Tables, figure, and references