Three groups of patients were compared statistically: 79 with the diagnosis "psychosomatic headache" (in the strict sense of the term), 450 others whose headache was part of another disorder (termed "symptomatic headache"), and 850 patients free from headache symptoms. The following characteristics were found for the group with psychosomatic headache: More psychosomatic diseases in the family, usually the eldest in birth rank, usually living in towns, married, two children, intellectual level about average, overweight, ego-strength with compulsive features, tendency towards oral abuse of different kinds, few other psychosomatic complaints (contrary to the group with symptomatic headache). In the discussion the authors try to demonstrate the defensive function of this selective somatisation.