A study was made of 35 patients with tumors of the renal pelvis. Tumors were indipendently graded and staged by a newly proposed method. The method of staging correlated well with grading of renal pelvic tumors and bore a direct relationship with prognosis. The high incidence of associated urothelial tumors, especially on the involved side, mandated radical nephroureterectomy including a bladder cuff as the treatment of choice.