Adolescence is a period of transition characterised by changes; in it the adolescent may go through moments of imbalance and extreme instabilities, a fact that may directly influence his repertoire of social skills, as well as his self-concept, influencing his behaviours, conducts and social relationships. The present research aimed to verify the level of self-concept and social skills of adolescents in conflict with the law who are serving a socio-educational measure at the Provisional Socio-Educational Care Centre (Casep). Five adolescents in conflict with the law serving socio-educational measures at Casep aged between 14 and 16 years were included as subjects. The instruments used were: the Child and Adolescent Self-Concept Scale (EAC-IJ), the Inventory of Social Skills for Adolescents (IHSA-Del-Prette) and a semi-structured interview. The present study found that although adolescents had a high self-concept, in general they had a low repertoire in social skills, confirming what has already been described in the literature regarding adolescents in conflict with the law.