Thirty-one renal allografts placed in 25 recipients with renal failure from biopsy-documented focal segmental glomerulosclerosis (FSGS) were reviewed. These represent all of the cases with this renal histology transplanted over 13 years. Recurrence of the lesion was demonstrated histologically in five recipients. A nephrotic syndrome occurred in all five patients and failure of the graft in two. Of 20 recipients who did not show a nephrotic syndrome, allograft histology in 12 did not show FSGS in any. From these data and a review of the literature, the risks of transplantation in patients with FSGS are assessed. Recipients under the age of 15 and with a course into renal failure of less than 3 years show recurrence in about 50% of cases. Of this 50%, about one-half will lose their grafts from the recurrence within 5 years, but some may show good function for many years, despite proteinuria or a nephrotic syndrome.