Sweden's first, and so fat only, ESWL unit for kidney stone treatment became operational on April 1, 1985. This paper presents some intermediate results from an integrated medical, economic, and technical evaluation of the new technology. Seventy-eight percent of 477 patients were defined as successfully treated, totally stone free or fragments less than 4 mm in size, after a follow-up of four weeks. After six months, the share of successfully treated patients had increased to 82%. Successes were closely related to the stone situation; the smaller the stone, the greater success of treatment. Patients' experiences with treatment were also studied and showed that less than 5% of the patients perceived the treatment as unpleasant, frightening, and/or time consuming. Epidemiological data reveal that one unit can replace all open surgical operations on the kidney.