Results in this study demonstrate that HLA matching has a beneficial effect on the survival of renal allograft in pediatric recipients. The introduction of a child-match procedure may have led to a lower degree of HLA well-matched grafts because of the small size of the pediatric waiting list. The poor results obtained in the group of children aged less than 6 years may have been due to a difference in physical condition at the moment of transplantation. This may explain why 4 of 20 (20%) of the failures in that age-group were due to patient death. The best results with the child-match procedure were obtained if the donor and recipient were both aged between 6 and 15 years. The overall graft survival in all children was improved by the use of Cs. An increase of approximately 10% was observed in this group of patients. The numbers in this group are too small, however, to permit any meaningful analysis of the influence of Cs on HLA matching. Finally, the overall results in this report demonstrate that renal transplantation is an effective form of therapy for end-stage renal disease in children.