Substance abuse is an expensive problem facing the American public and the criminal justice field. Using secondary data analysis this study examined 1,921 participants across five substance abuse programs within California and New York jail systems. Specifically this study explored the impact of location, demographic characteristics, offense committed, and previous drug treatment on successful completion of the treatment program. Descriptive analyses were used to examine the demographic characteristics of the sample and the types of drugs used by participants in the thirty days prior to jail admission. Results from bivariate analyses indicated that location, demographic characteristics, and previous drug treatment were all significantly related to successful completion. Implications for current correctional treatment programs and future research on this topic are discussed