Forty-seven patients treated by at least 28 days of thoracic duct drainage (TDD) before cadaveric renal transplant are compared with 63 patients treated with standard immunosuppression. The TDD patients were begun on half the dosage of steroids, and at 30 days were receiving approximately two-thirds the dose that the non-TDD patients received. Acute rejection occurred in 35% of the TDD group, as compared with 61% of the non-TDD group. Graft survival in the TDD patients was twice as good as the non-TDD patients at all time intervals. The patient survival rates were not significantly different between the two groups. TDD pretransplant favorably affects cadaveric renal allograft survival for at least five years.