The analysis showed that cases that had a drug or alcohol offense as the most serious charge made up 14 percent of the cases. Drug cases were more common in large counties, but alcohol cases were more common in small ones. In addition, juvenile courts responded formally to drug or alcohol cases much less often than to other delinquency cases. Moreover, courts were more likely to handle drug cases formally than alcohol cases. Drug possession cases and drug trafficking cases were equally likely to be processed formally, but cases of driving under the influence were more likely to be handled formally than other alcohol cases. Furthermore, courts varied considerably in their handling of substance abuse cases. Findings suggested that policymakers may want to examine the criteria for determining when to use formal processing or when to use an informal response such as diversion to voluntary services. Figures.