From November 1970 to February 1972, a total of 33 cadaveric kidneys were transplanted into 32 patients. There were 17 lowrisk patients and 15 high-risk patients. Acute rejections were treated with high-dose infusion of methylprednisolone (750 mg) and cyclophosphamide (400 mg). Percutaneous renal biopsies were done frequently to diagnose rejection and follow its evolution. Five patients received kidneys from donors pretreated with cytotoxic drugs. The one-year patient and kidney survival is 93.8% and 81.8%. After 12 to 25 months' follow-up the patient and kidney survival is now 90.6% and 78.1%. In the low-risk group there was no mortality; one patient who received a damaged kidney was returned to hemodialysis and all the others are fully rehabilitated.