Cytokines are polypeptide mediators which act as communication signals among cells of the immune system as well as among other cells and tissues in the body. They are a heterogeneous and complex group and include interferons, tumor necrosis factor and chemokines. They play a key role inhomeostasis and in host defense and are involved in such inflammatory and autoimmune diseases such as rheumatoid arthritis as well as infectious diseases such as HIV infection and spetic shock. Modulation of the production and action of cytokines, as well as their exploitation of therapeutic agentshas been the object of intense and competitive research. This book overviews the field of cytokine research and describes the various approaches that have been taken to develop the pharmacology of these novel mediators. The pharmacology of cytokines is an exploding area which is entering theclinical arena. The book in the framework of the immunobiology of cytokines, examines the interactions with the cytokine system of a variety of compounds ranging from simple synthetic chemicals to biotechnological products. In addition to examining individual agents and approaches, the book examinesthe pathophysiology of individual body systems and analyzes specific contexts for the pathophysiology of individual body systems and analyzes specific contexts for the pathophysiology of these mediators as well as pharmacological approaches for their control.