In understanding delinquency in adolescence the key theoretical papers on the role of oedipal resolution and superego development remain essential and are summarized. To this we need to add our knowledge of trauma and of developmental deficit if we are to offer appropriate strategies for young delinquents and to be able to select those for whom therapy, intervention with the network or containment are appropriate. The defence of activity, commonplace in adolescence, becomes too easily enacted in the network around the delinquent and in the public domain, and thoughts are given on this process and on the roles open to the psychotherapist. (Contains 1 note.)