The self-report version of the Strengths and Difficulties Questionnaire (SDQ) was administered to two samples of 11-16 year olds: 83 young people in the community and 116 young people attending a mental health clinic. The questionnaire discriminated satisfactorily between the two samples. For example, the clinic mean for the total difficulties score was 1.4 standard deviations above the community mean, with clinic cases being over six times more likely to have a score in the abnormal range. The correlations between self-report SDQ scores and teacher--or parent rated SDQ scores--compared favourably with the average cross informant correlations in previous studies of a range of measures. The self-report SDQ appears promising and warrants further evaluation.