OBJECTIVE: Although it is estimated that serious emotional disturbance affects 9 to 13 percent of children and adolescents in the United States, there are few national data on the characteristics of this group. METHODS: This study used data for 13,579 youths from the 2001 National Health Interview Survey (NHIS) to describe the sociodemographic features and insurance coverage of youths with serious emotional disturbance living in the United States. Youths with serious emotional disturbance were identified through their scores on the Strengths and Difficulties Questionnaire, which was added to the NHIS in 2001. RESULTS: A large majority of youths with serious emotional disturbance were white and had income at 200 percent of the poverty level or higher. About 40 percent of youths with serious emotional disturbance had private insurance coverage, whereas Medicaid and the State Children’s Health Insurance Program provided coverage for about a third of youths with serious emotional disturbance. CONCLUSIONS: Although Medicaid is an important payer of mental health services for youths with serious emotional disturbance, private insurance is still the primary source of health coverage for youths with serious emotional disturbance and for the overall population of youths.