The film-based MASC test, developed to identify patients with Asperger’s, proved suitable for testing adolescents’ and adults’ social-cognitive competence. It differentiated young people with behavioural problems from those without (measured by SDQ) and showed significant differences between hyperactive adolescents and adolescents with behavioural problems; the hyperactive young people tended to select answers that indicated emotional overreaction to social information, while the young people with behavioural problems were more likely to give emotional content too little weight or ignore it altogether. The MASC shows satisfactory reliability, has a challenging character for young people, and is-in contrast to empathy questionnaires-not susceptible to subjects’ tendency to provide socially desirable answers.