________________________________________ ABSTRACT: This paper is a narrative, exploratory, descriptive, and investigative profile of Borderline Personality Disorder (BP). Its purpose is to expand the existing description of behavioural characteristics of this disorder and to include a deeper emotional and interpersonal understanding of borderline symptomatology. The self and object-relations schools are recognized but treated as being limited to the post-birth biographical experiences. This study includes the expanded perinatal, preconception, transpersonal elements and interpersonal aspects of Borderline Personality etiology. BPs are characterized by lack of emotional commitment, hypersensitivity, feelings of emptiness and worthlessness, submissiveness, defense mechanisms of splitting and projection, and a strong need to control. Relationships have an "on the brink" and destructive quality. Repetitive cycles of regressive behavioral patterns are present. Excessive superego demands are combined with a deflated false self. Feelings are not discharged easily. The borderline has a deep, underlying terror of catastrophic annihilation, which may have its earliest roots in trauma surrounding the blastocyst's need to connect to the uterine wall and even to trauma surrounding conception, involving the egg's rejection of the sperm. Consequently borderlines may be hypersensitive to withdrawal and yet insensitive as to how their behavior affects others. Besides prenatal rejection, childhood abuse and generational factors play a part in forming the BP. The process of therapy is long term because of the chronic nature of the disorder, and the therapist must take into account the BP's terror and fragility during the release of Pain. However, treatment can be very successful and motivational and can lead to achieving workable and happy lives. This happens by releasing the Pain, regaining identity in the real self, and, through the therapist's acceptance, eventually gaining the self-acceptance which alone is capable of overcoming the inordinate en utero survival demands and abandonment that they experienced.