Past, present, and future aspects of histocompatibility.

We have stressed problems attendant on studies of the MHC, ignoring non-HLA factors and their role in allograft immunity. Many other topics could have been chosen for discussion is any such overview; our selection reflects our own interests. We felt assured, however, that excellent coverage by our many colleagues of the diverse and varied aspects of histocompatibility not approached in this summary has allowed us this freedom.