Four hundred sixty-seven patients with symptomatic upper urinary tract calculi underwent extracorporeal shock-wave lithotripsy (ESWL) at The New York Hospital-Cornell Medical Center during the first year. Ninety-five percent of stones were completely treated with one ESWL session. An analysis of 300 treatments revealed that the overall stone-free rate (success) three months after treatment was 75% The stone-free rate for patients with renal pelvic calculi less than or equal to 20 mm in diameter was 91%. Individual patient stone-free rates depended on stone size (burden), position, composition, and quality of disintegration. Two percent of treatments failed to disintegrate the targeted stone. Complications were minimal. Seven percent of treatments were followed by a secondary endoscopic procedure to facilitate complete stone passage, and 23% of treatments were preceded by cystoscopy with ureteral stent placement or manipulation of stones. Combined therapy utilizing percutaneous surgery or multiple sequential ESWL treatments is necessary for complex stones, and ureteroscopy or basket extraction remains the treatment of choice for distal ureteral calculi.