Psychoanalytic case material is presented to illustrate how mother-son incest may be involved in the pathogenesis of a particular subtype of narcissistic personality disorder. Male patients with this disorder have a grandiose view of themselves as entitled to occupy a special position with others, combined with a paranoid tendency to anticipate imminent betrayal. The enormous guilt related to perceived oedipal transgressions leads these patients to fear retaliation from an enraged, vindictive, and castrating father at any moment. In addition, these men often feel that their special role vis-à-vis mother is a precarious one contingent on doing her bidding. Hence, they also live in dread of an impending disaster involving either abandonment or humiliation by their mothers.