Objective: The goal of this study was to examine normalization of functioning among youths with persistent attention-deficit hyperactivity/disorder (ADHD) symptoms. Research design: Subjects were 85 referred boys with persistent ADHD as defined by the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition (DSM-III-R) who were followed up prospectively into mid adolescence and 68 boys without ADHD. These subjects were assessed at baseline and follow-up visits by using measures from 3 domains of functioning: school, social, and emotional. For each of these domains, we defined boys with ADHD as having normalized functioning if they attained scores above the 5th percentile of scores in the non-ADHD group. Results: Twenty percent of boys with ADHD were functioning poorly in all 3 domains, 20% were functioning well in all 3 domains, and 60% had intermediate outcomes. Increased exposure to maternal psychopathology, larger family size, DSM-III-R psychiatric comorbidity, and symptoms of impulsivity were negatively associated with normalization of functioning among children with persistent ADHD. Conclusion: Our results show that children with ADHD have a variable emotional, educational, and social adjustment despite syndromatic persistence. This suggests that normalization of functioning and syndromatic persistence of ADHD may be partially independent. (J Pediatr 1998;133:544-51)