OBJECTIVE: To compare prevalence of serious emotional and behavioral problems and mental health contacts for these problems among American and British children and adolescents. METHOD: Data on children and adolescents ages 5 to 16 years were drawn from the 2004 U.S. National Health Interview Survey (response rate = 79.4%) and the 2004 survey of Mental Health of Children and Young People in Great Britain (response rate = 76.0%). Emotional problems, hyperactivity/inattention, and conduct problems were assessed using the parent version of the Strengths and Difficulties Questionnaire (SDQ). Psychometric properties of SDQ scales were compared across countries. RESULTS: The SDQ has similar psychometric properties across countries. More British than American children met the criteria for emotional and conduct problems, but not hyperactivity/inattention. Prevalence was higher for all problems in 5- to 8-year-old British boys and for emotional problems in 13- to 16-year-old British girls. American children with serious emotional and behavioral problems had a higher prevalence of mental health contacts overall and with mental health providers but not with general medical providers. CONCLUSIONS: British children have a higher prevalence of parent-reported serious emotional and behavioral problems than American children. However, British children with these problems are less likely than American children to receive mental health care.