The Strengths and Difficulties Questionnaire (SDQ) is a brief behavioral screening questionnaire that can be completed in 5 minutes by the parents or teachers of children aged 4 to 16; there is a self-report version for 11- to 16-year-olds. In this study, mothers completed the SDQ and the Child Behavior Checklist (CBCL) on 132 children aged 4 through 7 and drawn from psychiatric and dental clinics. Scores from the SDQ and CBCL were highly correlated and equally able to discriminate psychiatric from dental cases. As judged against a semistructured interview, the SDQ was significantly better than the CBCL at detecting inattention and hyperactivity, and at least as good at detecting internalizing and externalizing problems. Mothers of low-risk children were twice as likely to prefer the SDQ.