The personality traits of 40 women with non organ-specific dysimmune diseases were studied by means of a questionnaire devised to evaluate behavioural components including 48 items divided into 8 different patterns. The patients fell into 3 groups. Group I comprised 20 women with collagen diseases, including systemic lupus erythematosus (n = 8), scleroderma (n = 4), Sharp's syndrome (n = 4), polymyositis (n = 3) and Shulman's syndrome (n = 1). Group II was made of 10 women with either primary (n = 6) or secondary (n = 4) Sjögren's syndrome. Group III consisted of 10 women with vasculitis. Results were compared with those obtained in a control population of 41 women without dysimmune disease. At the time of examination the mean daily dose of prednisone was 10.5 mg. All 40 patients differed from the control group by their unobtrusiveness, self depreciation (P less than 0.01), hyperconformability and excessive kindness (P less than 0.02). Additional traits were a tendency towards contradiction and intolerance in patients with Sjögren's syndrome and a lack of agressiveness combined with a feeling of inferiority in patients with vasculitis. These results confirms that patients with dysimmune disease are psychologically fragile and suggest that the possibility of psychotherapy should be examined in these patients.