All the clients completed a self-report instrument measuring adult ADHD-related behaviors, as well as a structured intake interview. Seven composite measures were selected from the intake interview, six of which were related to the probationer's family of origin, and the seventh to self-reported reasons for drug use. The ADHD symptoms scale used here demonstrated good psychometric abilities, was easily administered, and showed predictable validity. Thirty-one percent of probationers reported having recent symptoms of ADHD; they were likely to have experienced more severe problems than their counterparts, in terms of unemployment, number of previous arrests, violent behavior, use of cocaine, and conflict with parents. 4 tables and 18 references