Objective: To examine whether ADHD gender patterns with respect to social-demographic characteristics, comorbidity, and impairment vary as a function of service use for emotional or behavioral problems. Method: Two hundred and seventy-nine males and 119 females meeting ADHD symptom criteria identified in a nationally representative sample of Australian youth ages 6 to 17 are stratified according to whether they had attended a service in the previous 6 months. Results: ADHD gender patterns vary across service use on only 2 of the 31 comparisons made. The two exceptions were child's age at interview (females were older than males among service attendees but younger among nonattendees) and depressive disorders (females had higher rates than males among service attendees but lower rates among nonattendees). Conclusion: Systematic differences in methods of case identification rather than sample source may be responsible for the discrepant ADHD patterns found between clinic and community-based studies. (Contains 5 tables.)