From a phenomenological perspective, borderline disturbances are situated on the boundaries between neuroses, psychoses, and the more serious character disturbances. In this paper the author attempts to delineate the syndrome, from a differential-diagnostic viewpoint, as an entity in itself. She integrates Kernberg's theory of the borderline personality organization with other theoretical approaches and with hypotheses of her own. According to Rohde-Dachser, the development of the borderline structure is initiated in the second to third year of life through a traumatization of the infantile striving for autonomy. This results in a specific pathology of the ego in which primitive splitting defenses predominate.