Background: Although optimization of immunosuppressive schemes in renal transplantation have minimized acute posttransplant complications, long-term outcomes are still not optimal and most of the chronic graft damage is drug-related. Therefore, to define the best long-term maintenance immunosuppressive regimen is of major importance in renal transplantation. To assess this objective, we undertook a large, multicenter cohort study in Italy. Methods: We retrospectively analyzed data of 5635 patients (enrolled from 1983 to 2012) and we assessed the impact of 3 major immunosuppressive regimens (calcineurin inhibitors+antimetabolites+corticosteroids [CNI+ANT+CS] vs CNI+mammalian target-of-rapamycin (mTOR) inhibitors+CS [CNI+mTOR-I+CS] vs CNI+CS) on long-term clinical outcomes by employing several statistical algorithms. Results: The overall difference in the incidence of outcome over time was not statistically different within the first 5 years of follow-up (P =.13); however, it became significant at 10 years and 20 years (P