This book contains 32 chapters based on the corresponding papers delivered at the International Symposium on Antimicrobial Agents and Immunity, held in Siena, Italy on May 2-4, 1985 as a Satellite Symposium of the Third International Conference on Immupharmacology, held in Florence, Italy on May 6-10, 1985. As editors we express our profound appreciation and gratitude to the authors who have contributed so richly to this volume, and we think that it may t be too much to hope that a new cadre of investigators and students will share this gratitude for these records of experience and insight into antibiotic and host-parasite interactions. We owe a very special gratitude to Mrs. Christine Abarca for her outstanding editorial assistance in the preparation of this book. Andor Szentivanyi, M.D. University Distinguished Professor Departments of Pharmacology and Internal Medicine University of South Florida College of Medicine Tampa, Florida Herman Friedman, Ph.D. Professor and Chairman Department of Medical Microbiology and Immulogy University of South Florida College of Medicine Tampa, Florida Gunther Gillissen, M.D., Ph.D. Professor and Chairman Department of Medical Microbiology Faculty of Medicine RWTH, Aachen, F.R.G.