The implacable excited source of the drive insists and the borderline state, with its overflows, shows the importance of continuing to take account of the necessities and vicissitudes of psycho-sexual development. In this sense, what is needed is the defence of time - certain periods of latency, certain indeterminate intermediaries - and that of a therapy that includes the affectionate trend, the present time, which seems to synthesize the contemporary issues of care. The affectionate trend constitutes a model for thinking about the origins of borderline modes of functioning as much as the relational forms of institutional care - the life impulse that reanimates the psychic activity of the patient. On certain conditions discussed in this article, it also justifies the pertinence of mediations adapted to the body of the borderline adolescent. These mediations are demonstrations of caring tact, the quality of action marked by inhibition that serves to stimulate the capacity for reverie, auto-erotism and the transitional possibility of the patient.