Abstract
The identification of the intricate and multiple means by which the immune system serves as a principal impediment to solid organ graft survival has given rise to the development of an increasing number of highly effective immunosuppressive agents. At this point in time, additional ways of interrupting and negating the immune pathways have resulted in improved shortterm graft survival and lessened patient mortality. Unfortunately, immunosuppressive drugassociated toxicities still remain as a serious set of transplant morbidities and longterm graft survival is currently remaining at unacceptably high levels. As our understanding of the precise mechanisms of immune effector and enhancement mechanisms evolves there will be concomitant opportunities to develop agents that will specifically enhance graft survival with minimal complications to the host.