The study concluded that Criminal Justice Client Evaluation of Self and Treatment (CJ CEST) is a comprehensive instrument to effectively and efficiently measure client needs and functioning at intake. The CJ CEST is also appropriate for use in corrections-based drug-treatment programs to monitor progress over time. Monitoring drug abuse treatment delivery and progress requires the use of validated instruments to measure client motivations, psychosocial and cognitive functioning, and other treatment process dynamics. This study examined psychometric properties of the CJ CEST as part of the National Institute on Drug Abuse Criminal Justice Drug Abuse Treatment Studies project with a focus on examining client performance indicators for treatment of correctional populations. Analyses were conducted to address reliability of the CJ CEST scales at both the client level and program level. The sample included 3, 266 offenders from 26 corrections-based treatment programs located in 6 States. Consistent with earlier findings from community-based treatment settings, this study showed that the CJ CEST scales demonstrated good reliabilities at the client and program level as well as high test and retest reliability. Though results from confirmatory factor analyses indicated that some of the scales might represent more than one factor, evidence for construct validity was favorable. The findings support applications of the CJ CEST and Criminal Thinking Scales (CTS) within correctional treatment settings. Moving from clinical impressions to having objective scores for these client needs and functioning domains offers an empirically based progress monitoring tool. In an effort to maximize their role in practice, future efforts will examine their integration using automated scoring procedures into larger correctional information systems for the purpose of examining their combined use as a longitudinal measure and as a predictor of in-treatment and followup outcomes. Tables, references