Youth- and parent-rated screening measures derived from the Strengths and Difficulties Questionnaire (SDQ) and Development and Well-Being Assessment (DAWBA) were compared on their psychometric properties as predictors of caseness in adolescence (mean age 14). Successful screening was judged firstly against the likelihood of having an ICD-10 psychiatric diagnosis and secondly by the ability to discriminate between community (N = 252) and clinical (N = 86) samples (sample status). Both, SDQ and DAWBA measures adequately predicted the presence of an ICD-10 disorder as well as sample status. The hypothesis that there was an informant gradient was confirmed: youth self-reports were less discriminating than parent reports, whereas combined parent and youth reports were more discriminating-a finding replicated across a diversity of measures. When practical constraints only permit screening for caseness using either a parent or an adolescent informant, parents are the better source of information.