The author describes the successful psychotherapy of a patient who suffered from near psychotic epileptic twilight states. A cerebrally conditioned maturational arrest brought about an ego weakness which permitted only epileptic and hysterical forms of defense and discharge whenever stress situations occurred, as, for instance, in defending against archaic aggression. In the course of therapy the patient went from a negative oedipal inclination through a phase of phallic expansion to mature genital object relations.