Findings concluded that completion of the Sexual Offenders Treatment Program (SOTP), developed in Australia, did not have a measurable impact on recidivism over a 1-year followup period. Irrespective of engagement in treatment, the strongest predictor of recidivism is a history of committing violent or sexual offenses. If resources are going to be allocated to the treatment of sexual offenders, offenders with the highest probability of reoffending, for example violent offenders or repeat sexual offenders in particular, should be targeted for initial interventions. This valuation was severely limited by the relatively short followup time and missing portions in the available data. Current evidence suggests that if evaluation of program effectiveness is to be undertaken, it is essential to track offenders for up to 10 years following their release into the community or graduation from community-based treatment programs. Otherwise, it is not possible to assess the impact of the criminal justice system in general, and applied interventions in particular, on offenders. More specific questions relating to the psychological variables that predict treatment outcome were unable to be answered, nor were risk analyses for the group as a whole or specific subgroups within the sample able to be undertaken. It is important to develop and implement systems that track offenders over extended time periods and collate sufficient data to use newer methodologies. The completion of a survival analysis of offenders should also be priority in any future evaluation. Data were collected from 281 prisoners, released from custody during the evaluation period in 1992 to 2001; 85 participants failed to complete the program for reasons previously outlined. Tables, figures, references