The main purpose of drug courts is to use the authority of the court to reduce criminal activity by changing clients' drug-using behavior and potentially reducing post-program recidivism. Results on completion rates indicate that of the 124 drug court clients in the study population, 44 percent graduated. Within the first 2 years, the graduation rate rose and has since remained above 50 percent. Results on recidivism indicate that drug court graduates had lower total post-program recidivism than comparison groups (i.e. revoked probationers (pilot group) and other offenders referred to drug court who did not enter the program (referred group)). In terms of recidivism, the drug court appeared to work best for felons. In relation to cost, the results indicate that when controlling for the seriousness of entry crimes and referral type, the total corrections system costs for drug court clients was less than the comparison groups, both the pilot and referred group. Overall, drug court clients received more drug treatment than the comparison groups. Lastly, a year after the referral quarter, the treatment costs of drug court clients appeared to have stabilized, but at a lower level than the comparison groups, suggesting a positive long-term effect from the intensive treatment received in the early months of drug court participation and/or a positive effect from the drug court process and supervision. This report presents the results of an evaluation conducted on the Polk County Drug Court and supported by the U.S. Department of Justice, Bureau of Justice Assistance. The study focused on the period between August 1996 and September 1998 to enable a study of recidivism. Tables and appendixes A-Q