The extracorporeal treatment of stones in the kidney or ureter has now been successfully transferred to the United States. Introduced in Munich a few years ago, focused high-energy shock waves are used to fragment upper-tract calculi. The anesthetized patient is suspended in a water bath that transmits the energy pulses. Chaussy and Schmiedt 1 now report that 885 of the last 1,000 patients so treated became stonefree after a single treatment. Large stones often required a second or third session. Overall, 96% of calculi are completely disintegrated. The fragments produced are typically small and are passed with little pain or need for analgesics (C. Chaussy, MD, oral communication, February 1984). Stones in the ureter may quickly become impacted. If they cannot vibrate, the high-energy lithotripser may not be able to fragment them. These can often be retrieved with grasping forceps through the ureteroscope, however, and can be passed transurethrally to