The metapsychological status of adolescence as a psychoanalytic concept becomes meaningful with the definition of adolescence as already described by the author in his previous works.
Hence, the clinical approach evidences the insufficiency, on the one hand of the traditional conceptions according to which the use of the concept of symptom aims at multiplying personality profiles in the new psychopathological group of borderline states and, on the other hand, of the approach as described within the structure of the borromean knot as suggested by lacan.Resting on his latest works on the borderline state conceived as a « state » rather than as a « structure », hence being liable to be present in any structure, and which rests on the concept of « limit », the author insists on the distinction between behaviours and symptoms at adolescence and suggests that adolescence should be considered as a logical time of construction for the sinthôme and borderline states as provisional or fixed states that are specifically unstable of such a sinthôme. He here closes his paper with a few notes on the study of the qualities of such a sinthôme.