Between April 1987-March 1989,19 one-stage percutaneous nephrolithotomy were performed in our clinic. The stones of our patients were pelvic and solitary, and their sizes varied between lxl cm. and 4x2 cm.The procedure was done under general anaesthesia in 15 patients and high epidural anaesthesia in the remainder four. Our choice as dilatation technique was either Amplatz sheath (n=12) or balloon dilatation (n=7). We disintegrated the stones with ultrasound or electrohydraulic lithotripsy and took them out with forceps. A Malecot nephrostomy tube was left in place until ceasing of hematuria.We did not face any serious complications and we discharged 13 patients as stone-free achicvcing a complete clearence rate of 68.4 %.