Surveys in other countries suggest that children and adolescents experience high rates of mental health problems, however in Australia there has been no information at a national level about the prevalence of child and adolescent mental health problems. The Child and Adolescent Component of the National Survey of Mental Health and Well-Being is the first survey to investigate the mental health and well-being of children and adolescents at a national level in Australia. It provides an accurate estimate of the prevalence of mental health problems among children and adolescents in Australia. It also provides information about the degree of disability associated with mental health problems and the extent to which children and adolescents are receiving help for their problems. Information was collected from children aged 4-17 and their parents. Children and parents completed questionnaires assessing mental health problems (assessed using the Youth Self-Report and Child Behaviour Checklist) health related quality of life, health-risk behaviour and service utilisation. In addition, parents completed a face-to-face interview (3 modules from the Diagnostic Interview Schedule for Children) designed to identify Depressive Disorder, Attention Deficit/Hyperactivity Disorder and Conduct Disorder. Background variables include age, sex, metro/rural, parents employment/ education/income.