The paper describes three stories of children and adolescents with atypical gender identity development followed in psychotherapy. These cases have already been published, but are revisited here to show how these experiences contributed to the creation of the therapeutic intervention model of the Gender Identity Development Service originally established in 1989 at St George’s Hospital, London. The service transferred to the Tavistock Centre in 1996. The first case shows the gradual recognition of dealing with the development of an atypical gender identity rather than a psychiatric condition. Reflection on this case led to the definition of possible therapeutic goals. The second case illustrates the difference between solid and fluid identities, an important distinction in the decision to consider the possibility of physical intervention. The third case shows the network management model and addresses issues concerning autonomy.