From 1988 to 1990, we treated 13 children between the ages of 2 and 15 years with stones of the upper urinary tract. These stones were treated by means of 18 sessions of piezoelectric extracorporeal lithotripsy: 14 under general anaesthesia and 4 without even any analgesia. We obtained an 84.5% success rate with no particular adverse effects. These results are similar to those reported for hydroelectric or electromagnetic shock wave lithotripsy, which are associated with a higher morbidity. The efficacy of extracorporeal lithotripsy in paediatrics is remarkable, but clinical studies in adults as well as animal experimentations have demonstrated severe renal contusion and do not formally exclude the possibility of delayed complications. At the present time, this technique should therefore be used very cautiously and must be accompanied by systematic prevention of recurrent stones.