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. Estimates are based on data from the National Health Interview Survey, an ongoing national household survey of the civilian non-institutionalized population of the U.S. The analysis focuses on 23,051 children 6-17 years of age in a child sample from 2004, 2005, and 2006. Graphs.