The Psychological inventory of Criminal Thinking Styles (PICTS) was administered to program participants in two different federal prisons-a medium-security federal correctional institution and a maximum-security penitentiary-who were subsequently followed for a period of 24 months for evidence of disciplinary adjustment problems. Disciplinary outcome was measured by the total number of incident reports, the number of nonaggressive incident reports, and the number of aggressive incident reports received during the 24-month follow-up. Negative binomial regression was used to test the relationship between the eight PICTS thinking style scales and three disciplinary outcome measures because the total and nonaggressive disciplinary report distributions showed signs of overdispersion. The only PICTS thinking style scale to achieve statistical significance in this study was the Cutoff scale that successfully predicted total, nonaggressive, and aggressive incident reports in both samples.