Tools to assess the concept of criminal thinking have not often been tested in community corrections populations. This article examines the psychometric properties of the Texas Christian University Criminal Thinking Scales (CTS) in a sample of drug-using probationers ( n = 250) participating in a randomized trial. A confirmatory factor analysis found that three of the subscales may not be measuring distinct concepts and that most of the subscales do not distinguish between male and female offenders despite large differences in offending histories in these populations. Concurrent and predictive validity results demonstrated a limited ability of the CTS to correlate with known predictors of recidivism or with follow-up data on criminal activity. The CTS scores did correlate with predictors of treatment processes, including treatment readiness and self-efficacy, indicating that those with higher levels of criminal thinking may be more difficult to engage in treatment and services. Measurement tools of criminal thinking are important to the field, and further work is needed to strengthen the existing tools.