This study examines outcomes from the first prison-based therapeutic community, for drug addicted offenders, implemented at the Sharon prison during 1994–1997. The article describes the program that took place and the process of treatment experienced by those who participated in the program. Using a Cox Proportional Hazard Regression Model (CPHRM) to calculate Hazard of Recidivism, a sample of 421 offenders who participated in the program was analyzed to evaluate program outcomes, while indicating factors that increase/decrease hazard of recidivism. Our findings from the CPHRM revealed that length of time in the program is one of the strongest predictors of hazard of recidivism. However, different from other studies which argue that “the more the better,” findings from this study question such an assumption. Additionally, findings from the above multivariate analysis suggest that criminal history (i.e. age on set, and number of prior arrests), significantly increase hazards of recidivism. Results of the study are discussed in regard to the increase in prison population, expected benefits of treating incarcerated offenders, and the legal aspects of prisoners' rights.