The findings indicated that social functioning changed moderately during the first 90 days of the TC treatment. Social conformity increased and risk taking decreased as TC treatment progressed over the first 90 days. Unexpectedly, hostility also increased during the TC treatment, which was troubling given that hostility was the only social functioning factor that predicted treatment dropout. The findings also revealed no significant association between social functioning and recidivism following treatment. Rather, 1-year recidivism was related to criminal history while 2-year recidivism was related to age. The results suggest that a modified TC treatment model had a limited yet positive impact on the social functioning of probationers during the first 90 days of treatment but did appear to increase hostility among the participants. The research methodology involved collecting questionnaire data on social history, criminal history, drug dependence, social functioning, treatment retention, and recidivism from 406 probationers mandated to attend the Dallas Country Judicial Treatment Center (DCJTC), a corrections-based, modified TC treatment program for drug-involved felony offenders facing long-term incarceration. The main indicators of social functioning--hostility, risk taking, and social conformity--were measured at program intake, 3 months into treatment, and 6 months into treatment. Recidivism data were drawn from the Texas Department of Criminal Justice-Institutional Division and included the arrest and incarceration records for all participants. Recidivism was examined for 2 years following TC completion. Data analysis involved the use of multivariate logistic regression models. Additional research is necessary to improve the understanding of social functioning during treatment. Figure, tables, references