This article reports an evaluation of a New South Wales Department of Corrective Services custody-based treatment program for adult male sexual offenders. A risk band analysis was used to compare observed and predicted sexual and violent recidivism rates in a sample of 117 treated and released offenders. Risk bands and predicted recidivism were determined using the Static-99 risk assessment measure. Results demonstrated that during an average follow-up period of 3.75 years, observed sexual recidivism rates were lower than Static-99 predictions for the overall sample (8.5 percent vs. 26 percent). The same pattern was observed for violent recidivism (12.8 percent vs. 36 percent). At each Static-99 level of risk (low, lowmoderate, moderatehigh, and high), observed sexual and violent recidivism rates were lower than predicted rates. These findings were consistent with the general consensus that well-implemented cognitivebehavioral treatment can have a positive effect on offending behavior. (Published Abstract) Tables and references