The Role of Products of the Histocompatibility Gene Complex in Immune Responses documents the proceedings of a conference held on 3-7 November 1975, which brought together an international group of scientists spanning three independent disciplines—genetics and immunogenetics, molecular biochemistry, and immunobiology—with clinical medicine overlapping these disciplines. This volume contains 42 papers organized according to the eight sessions held at the conference. The papers in Session I examined the genetics of the major histocompatibility complex. Session II presented studies on the biology of mixed lymphocyte interactions and cell-mediated cytotoxicity reactions. Session III discussed immune response gene systems while Session IV dealt with the genetic control of cell interactions. The papers in Session V covered idiotypic determinants on T cell receptors. Session VI investigated the properties of histocompatibility gene products involved in regulation of immune responses. Session VII focused on the biochemistry and immunocytology of cell surface products of the major histocompatibility complex. Finally, Session VIII discussed interrelationships between products of the major histocompatibility complex and their relevance to disease.