Even in the presence of extracorporeal shock wave lithotripsy there is still the need for endourological treatment of stones in the urinary tract. Stone fragmentation usually is achieved with either ultrasonic, electrohydraulic or laser lithotripsy. We report our early experience with a new, simply constructed machine at a reasonable cost for endoscopic stone disintegration--the Swiss Lithoclast. The principle of this lithotriptor is based on pneumatic shock waves induced by the central compressed air system of a hospital or by a compressor. This device was used to treat 151 patients with stones in the kidney, ureter, bladder or a Kock pouch continent urinary diversion. Endoscopic fragmentation was successful in all patients. Independent of the composition, all stones were disintegrated within a short period, indicating that the device may well represent an attractive alternative to standard endoscopic lithotriptors.