This report presents national estimates of the prevalence of diagnosed attention deficit hyperactivity disorder (ADHD) and learning disability (LD) in U.S. children 6–17 years of age and describes the prevalence of these conditions for children with selected characteristics. The use of educational and health care services and the prevalence of other health conditions are contrasted for children with ADHD without LD, LD without ADHD, both conditions, and neither condition.