Despite the remarkable improvement in short-term patient and graft survival among the recipients of kidney transplants, the progressive renal dysfunction (chronic allograft dysfunction) accompanied by chronic interstitial fibrosis, tubular atrophy, vascular occlusive changes and glomerulosclerosis remains the chief cause of graft loss. As a result of this damage from immunologic and non-immunologic injury, the long-term survival of kidney transplants has changed little during the past decade. And, among the non-immunologic factors, calcineurin inhibitor nephrotoxicity has been shown to be the most common factor leading to long-term graft damage and progression to graft failure. This is further supported by the previous finding that long-term use of calcineurin inhibitor-based therapy leads to deterioration in kidney function, even in recipients of non-renal organ transplants.