In the present study long-term morbidity, quality of life and over-all rehabilitation were assessed in 14 patients with a functioning renal allograft for 20 years or longer. Followup ranged from 20 to 27 years (mean 22.5 years). All patients enjoyed excellent and stable renal function, and the mean serum creatinine level at 20 years was 1.3 mg. per dl. Complications related to long-term immunosuppressive therapy comprised infection in 8 patients (57%), malignancy in 7 (50%), cardiovascular disease in 6 (43%), cataracts in 3 (21%) and avascular necrosis of the hip in 2 (14%). Over-all quality of life was excellent in 13 patients who were able to return to work, participate in pre-illness levels of activity and enjoy sexual activity. While successful renal transplantation allows patients with end stage renal failure to resume relatively normal lives, these patients remain prone to complications resulting from long-term immunosuppressive therapy.