This article addresses the relation between antisocial behaviour and social resources in a 2-year longitudinal study of 100 high-risk adolescents in residential care. Problem behaviour was measured with the Externalizing Scale of the Youth Self Report. Social resources were recorded using semi-structured methods. Hierarchical regression analyses showed interactions suggesting that the same variables can fulfil risk as well as protective functions: clique membership and satisfaction with social support fostered behavioural continuity. In contrast, a lack of social embeddedness had a risk effect for well-adapted adolescents and a protective effect for the deviant ones. Social resources were more influential in girls. Theoretical implications and methodological problems are discussed.