From 1956 to 1980 partial nephrectomy was done on 23 patients with localized renal carcinoma occurring bilaterally or in a solitary functioning kidney. The mean postoperative followup was 5.4 years, and the 5-year patient survival rates considering death of renal cancer only or of any cause were 70.2 and 59.6 per cent, respectively. Survival was diminished in patients with bilateral asynchronous renal carcinoma. Renal carcinoma recurred postoperatively in 6 patients (26 per cent), including 3 (13 per cent) with local recurrence in the renal remnant. Currently, 12 patients (52 per cent) are alive with stable function and no evidence of malignancy. These long-term data support the efficacy of partial nephrectomy for selected patients with renal carcinoma.