Although during the resolution of the oedipus complex main sexual identity and core body image are established, adolescence is the time when sexual wishes and oedipal identifications are integrated into an irreversible sexual identity. The main developmental function of adolescence is seen as the establishment of this final sexual organization. This thesis carries diagnostic, prognostic, and therapeutic implications: 1) correct diagnosis and treatment in adolescence can be critical for the patient's entire future life; 2) the view that intensive treatment in adolescence is contraindicated is incorrect; 3) criteria for distinguishing late adolescence from young adulthood can be formulated in terms of libido object directedness, integration of physically mature genitals into the body image, and detachment from the central masturbation fantasy of childhood.