There was a need to bring this information together in a single volume, as much of the key recent developments have been dispersed throughout the biomedical literature, largely in specialized journals. Since, as in the past, important developments in immunosuppressive therapy in one branch of medicine (. transplantation) are likely to benefit another (., dermatology, rheumatology, gastroenterology), cross-disciplinary coverage of the mechanistic basis of the various therapeutic strategies in a single volume is likely to convey the potential of advances in therapy in the most coherent manner possible. Hopefully, we will succeed in inducing interest and appreciation among the.