This study compared the antecedent and subsequent disciplinary adjustment of 203 male inmate graduates from a 20-week psychoeducational group entitled Advanced Gambling Lifestyle and 124 male inmate controls who had volunteered for the Lifestyle Change Program (LCP) but were transferred prior to the first group session. A repeated measures analysis of variance disclosed significant group and interaction effects when the total number of disciplinary reports served as the dependent variable, but not when gambling-related disciplinary reports were examined. Simple mean effect analysis of the total disciplinary report outcome determined that Advanced Gambling Lifestyle participants committed significantly fewer disciplinary infractions than control inmates during the follow-up, and only participants showed a significant reduction in disciplinary infractions over time.