We report our experience with extracorporeal lithotripsy (Dornier HM3) in a series of 26 children with a mean age of 11.6 years, treated for 3 1/2 years. 12 children (46%) had a previous history of calculi and 7 (27%) had already undergone surgery on the same side. Treatment requires two transducer investigations before lithotripsy. With the exception of minor modifications the technique is the same as in the adult. Three (9.7%) postlithotripsy complications were noted, requiring 2 drainage procedures to be carried out on the urinary tract. At 3 months, the success rate (no residual calculi on the plain abdominal film) was 60.7%. This study confirms the efficacy of lithotripsy in the treatment of urinary lithiasis in children.