Juvenile drug courts generally work with treatment and rehabilitation agencies to hold offenders accountable for their drug use and other illegal behavior; address social and behavioral problems related to offenders' substance abuse; support offenders and their families in developing positive community relationships and maintaining crime-free and drug-free lives; and ensure effective coordination of the justice system with related service providers. In order to examine differences among programs under this general model, six juvenile drug courts were studied in Charleston, SC; Dayton, OH; Jersey City, NJ; Las Cruces, N M; Missoula, MT; and Orlando, FL. The study was conducted by the Urban Institute during visits to each court during 2001 and 2002. The study involved document reviews, courtroom observations, and interviews with key stakeholders. The focus was on the composition of the drug court team, the procedures used for screening and assessing youth, the conduct of judicial hearings and how cases are coordinated, the use of rewards and sanctions, drug-testing procedures, and the provision of treatment and collateral services. Overall, the study found that operational structures and treatment approaches usually result from adaptive responses to the local context, notably the available resources, perceived gaps in services, and the need to manage increasing caseloads. Consequently, juvenile drug court practices vary significantly from court to court. This diversity is a major reason for the lack of theory-based drug court evaluations and the limited effect of evaluation results on drug court policies. Suggestions for juvenile drug court evaluations are offered. 1 figure and 8 exhibits