The literature on disease phobia is discussed and a controlled study of this variety of hypochondriasis is presented. There were 30 disease phobic and 30 control subjects, in-patients of a general hospital psychiatric unit in Sydney. Controls were defined as lacking the symptoms ‘disease phobia’, ‘disease conviction’, ‘somatic preoccupation’ and ‘psychogenic pain’. Matching was one-for-one and concerned sex, age and occupational prestige. In brief, the disease phobics were more anxious and self-pitying (current mental state). Before the illness they were more prone to inhibition of anger, bodily concern and low selfesteem (personality variables). As children they were more often weak, sickly and overprotected. Fifteen were youngest siblings versus only six of the controls. They gave a history of much family illness, substantiated by the findings of an excess of deaths among the mothers of disease phobics (life history characteristics). They reported an electrical current as a sensation at relatively low voltages and had low tolerance of pain (experimental measures). A logical insight into the origins of disease phobia is provided by inter-relating the data from these four aspects of the investigations (Fig. 1). This matrix is interpreted in terms of the augmentation-reduction theory of Petrie.