In the psychotherapy of personality disorders, the limitations of the self and of interpersonal functioning that underlie all personality pathology are both a main treatment focus and a major obstacle in doing so. These limitations are most intensely manifested within the primary aspect of the psychotherapeutic relationship. The core of personality disorders-identity diffusion-refers to a self, tormented by insignificance and annihilation, and by disconnectedness and mistrust. The infant will have internalized a mental state called the alien self that persists alongside an agentive self. This split leads to two domains of primitive dyadic object relations: one dominated by projection of epistemic yearning onto an idealized object, the other by projection of self-rejection onto a demonized object. The therapist remains an alien object in this way, making cooperation within therapy momentarily or even structurally impossible, with a negative impact on the working relationship, and a greater role of the realistic relationship.