The aim of this study was to evaluate whether specific cognitive aspects are present in patients suffering from somatoform disorders. With a sample of 493 patients from a center for behavioral medicine, the authors evaluated a questionnaire assessing typical cognitions concerning body perception, illness behavior, and health. The authors further examined 225 participants, including patients with a somatization syndrome, patients with somatization syndrome and additional hypochondriasis, patients with hypochondriasis, patients with other mental disorders (clinical control group), and nonclinical controls. The results showed that not only patients with hypochondriasis but also patients with somatization syndrome had cognitive concerns and assumptions that were specific for the disorder. These patients had a self-concept of being weak and unable to tolerate stress. A catastrophizing interpretation of minor bodily complaints found in hypochondriacal patients in earlier studies was also found for patients with multiple somatization symptoms.