This text aims to provide a complete understanding of the complex biological events involved in organ transplantation, allograft rejection and immunosuppression. The first section presents background information on cellular and molecular physiology and describes the techniques used in contemporary transplantation biology. The book then examines the antigen-independent and antigen-dependent host defence mechanisms evoked during organ transplantation, particularly the permutations of lymphocyte physiology. Also included are discussions of T- and B-cell tolerance and the immunosuppressive functions of the liver. The next section focuses on the manifestations of solid organ rejection. The final section examines immunosuppression and explores future methods for manipulating host responses to allografts and xenografts.