Azathioprine combined with a low dose of steroid (20mg of prednisolone) commencing the day following transplantation has been used for immunosuppression for 151 consecutive renal transplants in 141 patients (146 cadaver grafts, 5 living related donor grafts). Immunosuppression was satisfactory as 109 grafts function from 6 months to 10 years, 17 of 42 grafts lost failed from rejection. No patient died from infection before 90 days, 4 died later from infection, 2 associated with anti-rejection therapy. Seven patients developed gastrointestinal complications, 1 died; 4 developed diabetes, all survived; only 1 patient developed avascular necrosis of bone.