This study describes the utilization of surgical operations, frequency and outcome of medical and surgical treatment in a group of persistent somatizers compared with a control group of non-somatizers. The study was carried out using the Danish national medical register to identify persons in the general population (age range 17-49 yr) with at least 10 general admissions during an 8-yr period. Persistent somatizers were defined as persons with more than six medically unexplained general hospital admissions in their lifetimes before 1985. Conversely, non-somatizers were patients whose admissions could mainly be ascribed to well-defined somatic disorders. The findings show that persistent somatizers had been exposed to extensive surgery, outnumbering the non-somatizers. Surgical operations were of several categories, with gastrointestinal and gynaecological operations being the most frequent. The physicians used medical and surgical treatment nearly as often for treating persistent somatizers as in the treatment of the non-somatizers. Surgical or medical treatment was used in nearly half of the medically unexplained admissions. The outcome of the surgical treatment of the persistent somatizers was, however, generally unsuccessful in that the effect was unsatisfactory in three quarters of cases. Similarly, two thirds of the medical treatments were judged to be unsuccessful in persistent somatizers. The findings suggest that the costs of somatic diagnostic procedures and fruitless surgical and medical treatment attempts on persistent somatizers are enormous, and only exceeded by the risk of iatrogenic harm. This emphasizes the need for an early diagnosis of somatization and of treating it properly.