The influence of donor age and recipient age on outcome after renal transplantation has been investigated in numerous studies. There is some evidence that patient survival in elderly patients who receive a transplant is significantly higher compared with those, who remain on dialysis. In general, patient survival after renal transplantation is mainly dependent on recipient age and on comorbid conditions. Concerning graft survival, most studies conclude that the survival of kidneys taken from older donors (> 50 years) and very young donors (< 5 years) is reduced. Graft survival was also found to be reduced in very young recipients (< 5 years). Functional graft survival proved to be better in older recipients (> 50 years) as compared to younger recipients, due to a reduced immunologic response capability. Actual graft survival however, where cases of death with functioning graft are included, is fairly equal in both populations. The question, whether the age difference between donor and recipient has an influence on graft survival, needs to be further investigated. In conclusion, donor and recipient age are important risk factors, which may influence outcome after renal transplantation and therefore should be considered carefully.