This topical insight in the role of cytokines in joint inflammation and destruction helps to better understand key processes in diseases such as rheumatoid arthritis and osteoarthritis. Apart from the impact of cytokines on joint tissues, various chapters address targeted therapy with biological response modifiers and future interventions with carefully designed inhibitors. Special attention is given to elements of synovial cell activation, cell-cell interaction, cytokine interplay, and mechanisms of cartilage destruction and bone erosion. New information on the cytokines IL-15, IL-17 and IL-18 and their position in the complex cytokine interplay and an outline of the role of established cytokines, such as TNF, IL-1 and IL-6, is provided. Cytokine regulation of destructive enzymes, RANKL, the endogenous inhibitor OPG and their crucial roles in joint erosion are highlighted. This volume gives a complete and balanced view on pivotal cytokines and joint pathology for the biomedical and clinical researcher.