In analogy with previous observations in native kidney disease, Grimm et al. recently reported that interstitial fibrosis in protocol biopsies of renal allografts, at 6 months post transplantation, significantly inversely correlates with the subsequent graft survival One hundred recipients of a first renal allograft will be randomized to an immunosuppressive protocol based on cyclosporine (50 patients) or sirolimus (50 patients). Concommittant immunosuppression will be similar in both groups, and consists of Daclizumab as induction treatment (five iv gifts every two weeks), and mycophenolate mophetil and steroids as maintenance immunosuppression.