The purpose of this study is to better characterize graft and patient survival posttransplantation by examining survival according to underlying renal disease for all first-time renal allograft recipients in the United Network for Organ Sharing (UNOS) registry. From 1987 through 1996, the UNOS registry collected data on 23,838 living and 67,183 cadaveric renal transplantations. This investigation included all patients undergoing their first renal transplantation for whom the underlying cause of renal failure could be identified and categorized. Gross 1- and 3-year patient and graft survival according to underlying renal disease are included. In addition, a Cox proportional hazards model was created to analyze the effect of underlying disease on graft and patient survival after adjusting for comorbid conditions, demographics, and type of renal transplant (living versus cadaveric). The association between underlying disease and graft and patient survival is shown. Amyloidosis, sickle cell anemia, scleroderma, and radiation nephritis are associated with poor graft and patient survival. The risk ratio for patient mortality was more than twice that for immunoglobulin A nephropathy for a number of conditions, including analgesic nephropathy, amyloidosis, and both forms of diabetes mellitus.