This study aimed to further evaluate previous findings regarding drug use and criminal behaviors among the criminal population by investigating the effectiveness of two Colorado Residential Substance Abuse Treatment Therapeutic Communities (RSAT TC) for offenders. The first, the Crossroad to Freedom House Therapeutic Community at the Arrowhead Correctional Center (ACC TC) was a prison-based program. The second was the community-based Peer I Therapeutic Community (Peer I). Two methodologies were used to gather data. Part 1, RSAT Outcome Data, contains quantitative data collected from five separate study groups of differing sample sizes that received differing levels of treatment, with a total of 778 cases. The groups were compared on five separate outcome variables: technical violation, new misdemeanor arrest, new felony arrest, return to prison, and overall supervision failure. To gather baseline information from participants, a researcher administered the intake packet in group format to participants within three weeks of admission to ACC TC. After completing the treatment programs, outcome data were collected for a two-year follow-up period for each participant. Part 2, Case Studies, consists of case studies of ten participants, two from each of the above five listed groups. One from each group had successful outcomes, and one did not. Successful outcomes were defined as participants who were still living in the community after 12 to 18 months without any new charges. Unsuccessful outcomes were defined as those participants who were returned to prison for technical violations or new charges and were eligible for study only if they had been living in the community for six to twelve months before returning to prison. Information for the case studies were gathered through interviews with both former prisoners and one of their significant others. Variables for Part 1 include demographic information, length of stay in both the ACC TC and Peer I, types of programs parolees were released to, and time period between leaving the Department of Corrections and any subsequent returns. Information was also gathered on the presence of psychological concerns as an adult, as well as in childhood. Part 2 consists of information regarding ACC TC and Peer I participants' post-treatment such as their employment status, financial well-being, significant relationships, relapse information and whether or not the interviewee has returned to the Department of Corrections since receiving treatment and being released.