Summary Pruritus ani, although it presents as the only symptom, never occurs alone, but is associated with bizarre gastrointestinal symptoms and sexual disorders. Depressive and paranoid trends are common. It is the leading symptom in a syndrome. This syndrome exists in its own right. No distinct personality type could be established; it was found to occur without personality disorder, in psychoneurotic and prepsychotic personalities, and in frank psychoses. Its origin can be traced to a reactivation in adult life of infantile (unconscious) fantasies about procreation centering round the anal function, which precede genital interest and knowledge of sex. These "cloacal" fantasies are revived in their original primitive mode, as bodily sensations rather than ideas; the symptoms thus represent the fantasy. They appear as distressing somatic symptoms because such archaic fantasies are incompatible with reality. A breakthrough into consciousness is thus prevented and psychotic delusions avoided. Revival of procreation fantasies must be more deeply disturbing in the man than in the woman; this is borne-out by the greater severity, longer duration, and preponderance of male cases. The syndrome is capable of reduction by psychotherapy. The structure of this syndrome is simpler than that of the psychoneuroses. By the absence of overt anxiety it can be separated from anxiety hysteria, and by the absence of true obsessions, with their tendency to displacement and spread, from obsessive-compulsive neurosis. Secondary gain is absent. Its psychopathology suggests a hypochondriacal syndrome with specific content. Freud classed hypochondria among the "actualneuroses" to which psychoanalysis had little to contribute. In psychiatry proper hypochondria is also a stepchild. Brachet speaks of it as a "disorder of the imagination." Gillespie8 defines "the syndrome of hypochondria" as, "A mental preoccupation with a real or supposititious physical or mental disorder, a discrepancy between the degree of preoccupation and the grounds for it, so that the former is far in excess of what is justified, and an affective condition best described as interest with conviction and consequent concern, and with an indifference to the opinion of the environment, including irresponsiveness to persuasion… usually inaccessible to psychotherapy… it affects men predominantly… it can shade into schizophrenia… in its mild form it is often erroneously diagnosed as anxiety neurosis or hysteria." This description neatly condenses our findings on patients with pruritus ani. It should perhaps be added that in the clinical example given by Gillespie of hypochondria there was, besides intestinal symptoms of "a bizarre nature" and "persecutory ideas of a peculiar kind referring to his gullet and genital organs, " also "a tearing away at the anus."