Since 1962, a series of studies have appeared in the psychiatric literature which define hysteria with increasing precision, differentiating that syndrome from the presence of conversion symptoms alone. Hysteria was described in a recognizable fashion more than a century ago by Briquet (1859). Some fifty years later, the syndrome was redescribed by Savill (1909). After a further period of nearly fifty years, Purtell, Robins and Cohen described hysteria as it occurred in a controlled series of patients (1951). Working from Purtell's clinical data, Perley and Guze introduced specific checklist criteria for the diagnosis of hysteria in 1962. These criteria defined a female population homogeneous in prognosis, a population to be distinguished from that defined by conversion symptoms alone. Conversion symptoms are seen in a variety of medical and psychiatric illnesses, and by themselves, conversion symptoms are of little prognostic value (Gatfield and Guze, 1962; Perley and Guze, 1962; Slater and Glithero, 1965).