The psychoanalytic treatment of a young woman whose father had been killed in a concentration camp when she was four years old serves to illuminate certain aspects of libidinal and ego development, particularly as it touched on the effects of losing one's father just before entering the Oedipal phase and on the defensive use of denial in lieu of mourning. Further consequences of the patient's loss are seen in the extent to which it influenced the self-image, sexual identity formation, and superego functioning, especially with regard to the role of guilt.