Objective: The purpose of this study was to examine whether persisting hyperactivity into adulthood was associated with impaired family, friendship, and partner relationships or poor coping skills in everyday life. Method: A 20-year community-based follow-up of 6- to 7-year-old boys showing pervasive hyperactivity (n = 40) and unaffected controls (n = 25) was conducted. At age 27 years, participants were assessed with detailed interview techniques as well as self-report ratings. Results: ADHD in adulthood was associated with problems in intimate relationships and negotiation skills. Antisocial behavior did not influence the association, but remitting childhood hyperactivity was not associated with social relationship difficulties in adulthood. Conclusion: In an untreated, community-based sample of hyperactive children, the risk for unsatisfactory social relationships is largely confined to those patients who still show ADHD in adulthood. The majority of patients who experience childhood hyperactivity have positive social relationships in adulthood. (J. of Att. Dis. XXXX; XX(X) X-XX)