The present analysis was undertaken to evaluate the influence of primary allograft nephrectomies on the early function, incidence of rejection, and short-term graft survival of subsequent renal retransplants. Among 95 consecutive cyclosporine treated retransplant recipients, 52 were retransplanted without primary allograft nephrectomy; 35 had removal of their primary grafts prior to retransplantation for fever and graft tenderness (30 patients) and persistent hematuria (5 patients); and 8 patients had an elective primary graft nephrectomy at the time of retransplantation. Demographic characteristics and immunosuppressive regimens were otherwise similar in all three groups. Nephrectomy of the primary allograft prior to retransplantation was associated with a significant subsequent rise in preformed cytotoxic antibody levels (57% having PRA greater than 30% compared with 33% in those with retention of primary grafts), a significantly higher incidence of delayed graft function among retransplants (63% compared with 30% in those who did not undergo primary allograft nephrectomy) and a trend toward decreased allograft survival in the subgroup who lost their primary allografts in the first year posttransplant. The incidence of acute rejection and 3-year posttransplant renal function in retransplants were not, however, influenced by nephrectomy of the primary allograft.