A patient with tuberous sclerosis and renal failure secondary to bilateral multiple hamartomas and clear-cell tumors of the kidneys had renal allotransplantation performed. A second patient with the same syndrome has undergone nephrectomy for hamartomas of the right kidney and has a large tumor mass in the remaining kidney. This patient will have a renal transplant when her status requires. In spite of a systemic disorder, we consider these patients good candidates to have transplants. Clearcell renal cancers in patients with tuberous sclerosis do not appear to behave as malignancies and do not offer a contraindication to transplantation. Children with bilateral Wilm's tumors and individuals with bilateral clear-cell tumors of both kidneys or of a sole functioning kidney may also greatly benefit from having a renal transplant.