Donor-recipient ABO blood group mismatching is associated with a decreased graft survival rate in liver transplantation. We have been unable to demonstrate an effect of high levels of panel reactive antibody or a positive donor-specific cytotoxic antibody cross-match on graft survival. A limited analysis of HLA-matching for the A, B, and DR loci suggests a paradoxical effect, but much more experience is needed before the true effect of HLA matching on graft outcome can be reliably evaluated.