Adolescence in psychotherapy - A. Freud e D. Meltzer both suggested a "turmoil" model of development which was also supposed to be a normative one. Hoffer’s and Rutter’s studies in non clinical populations have underlined also the presence of less conflictual models of development. Beside this attachment theory has given a great importance to early experiences so that both continuity and discontinuity of the development are at the moment taken into consideration .The author makes a brief summary of the various developmental tasks the adolescent has to confront with. and makes some considerations about the new neurobiological data (Weinberger,Elvevag e Giedd) on the adolescent brain .Some notes on setting and a posttraumatic stress disorder clinical case conclude the paper. Key Words: Adolescence, Developmental Models, Developmental Tasks, Setting, Posttraumatic Stress Disorder.