Research found that the Criminal Thinking Scales (CTS) might provide useful diagnostic information to help identify youth with problem behaviors that predict poor outcomes following incarceration while accounting for individual variations in response to treatment for incarcerated adolescents who receive treatment during reentry back into the community. A number of clinical trials have examined interventions designed to impact antisocial attitudes, mental health disorders, and substance abuse problems of adolescent offenders. These controlled trials have demonstrated efficacy for family and cognitive-behavioral interventions for improving substance abuse problems of adolescent offenders, but the interventions have produced substantial variability in outcomes. Forty percent of treated adolescents remained abstinent after 1 year, whereas 30 percent relapsed, and another 30 percent showed no improvement during treatments. These variations in outcomes were likely the result of differences in adolescent risk levels, especially those related to criminal thinking. The study findings underscore the importance of assessing adolescent criminal thinking, particularly in an effort to inform intervention assignments. The sample consisted of 151 male and 52 female adolescents who consented to participate in the study. In-depth interviews were conducted on these youths in a juvenile detention facility for an average of 167 days. The study not only found CTS dimensions had good reliabilities among adolescents, but the scores when compared to adult offenders suggested the use of the CTS as an instrument for predicting long-range behaviors of young offenders. Study limitations were discussed in detail. Tables, references