From March 1988 until May 1989, 361 patients with 438 stones were treated with the Dornier multipurpose lithotripter MPL 9000. 64.8% of the stones were situated in the calyx, 32.6% in the renal pelvis, 1.1% in the upper and 1.4% in the distal ureter. 19.6% of the stones were radiolucent. Multiple MPL treatments were performed in 10.2%. In 4.3% fragments post-ESWL treatment were larger than 5 mm. In 95.7% of the cases complete disintegration was achieved. 63.5% of the treatments were performed without using analgesia or anesthesia. Intravenous anesthesia was used in 20.5%. Analgesia and sedation in 13.6%, general anesthesia in 1.7% and epidural anesthesia in 1.1%. After 3 months' follow up 74.3% were stone-free. Residual fragments were found in the upper calyx in 1%, in the middle calyx in 5%, in the lower calyx in 13%, in the renal pelvis in 5.6% and in the ureter in 1%. The MPL 9000 has been proven to be similarly effective for the treatment of renal stones, while difficulties in localizing ureteral stones, while difficulties in localizing ureteral stones were noted. The major number of treatment was performed without any analgesia or anesthesia. No major complications were encountered. Due to the small focal area and the ultrasound location system. Special advantages were found for the therapy of children.