The concept of narrative identity implies a continuity of the personal past, present and future. This concept is essentially based on the capacity of persons to integrate contradictory aspects and tendencies into a coherent, overarching sense and view of themselves. In ‘mature’ neurotic disorders, this is only possible at the price of repression of important wishes and possibilities for personal development. Patients with borderline personality disorder lack the capacity to establish a coherent self-concept. Instead, they adopt what could be called a ‘post-modernist’ stance towards their life, switching from one present to the next and being totally identified with their present state of affect. Instead of repression, their means of defence consists in a temporal splitting of the self that excludes past and future as dimensions of object constancy, bonding, commitment, responsibility and guilt. The temporal fragmentation of the self avoids the necessity of tolerating the threatening ambiguity and uncertainty of interpersonal relationships. The price, however, consists in a chronic feeling of inner emptiness caused by the inability to integrate past and future into the present and thus to establish a coherent sense of identity. The paper outlines the concept of narrative identity and explores its disturbances in borderline personality disorder. Finally, the increasing prevalence of these disorders is linked to the development of a mainly externally driven, fragmented character in post-modern society.