The results suggest that approximately one third of participants in three misdemeanor drug court programs might have had relatively minimal drug use problems. These individuals classified as optimal performers based on their urine screen results were generally capable of achieving abstinence soon after entering the programs and remaining continuously abstinent for most of the ensuing 14 weeks. They were also significantly more likely to test negative for drugs at the 6-month follow-up and to successfully graduate from the programs. In addition, approximately two thirds of these individuals produced sub-threshold drug composite scores on the Addiction Severity Index (ASI), similar to a community sample of non-treatment-seeking individuals. This provides convergent evidence for the existence of a subgroup of individuals who might not have had a clinically significant substance use disorder. Data were collected from 284 adult drug offenders participating in 3 misdemeanor drug court programs in Wilmington, Dover, and Georgetown, DE. Figure, table, and references