Analysis of 463 consecutive primary cadaver renal transplants showed no influence of HLA match grade on renal allograft survival. Additional categorization according to HLA match grade and degree of presensitization again showed no correlation between match grade and graft survival. Mismatches and matches of specific antigens, cross-reacting groups of antigens, and effect of matching at both locus A and B were also evaluated. There was no significant effect on graft survival except when mismatches against donor A2 and cross-reacting group A2, A28 occurred. A trend toward better graft survival was suggested in recipients matched for A9 and cross-reacting group A9, Aw 23, Aw 24. Although HLA match grade did not influence ultimate graft survival, HLA typing remains important, especially to avoid mismatch against donor A2 antigen. In addition, subsequent detection of new specificities, particularly in other than the A and B loci, may provide significance in the future.