connective tissues are essential for the physical functioning of the animals's body. The condition of the various connective tissues is governed by biochemical factors, anabolism and catabolism, that are controlled by specific enzymes. Any change outside the normal range of metabolism, for instance induced by immunological reactions, may induce a pathological disturbance. The result can be acute or chronic inflammation, or loss of normal function, expressed in loosening, dilatation, breaking, wear, stiffness, shrinking, scars, stenosis, and cirrhosis or any other kind of fibrosis. A first step toward improving our understanding of the feedback mecha­ nism that maintains the biological status and texture of a given connective tissue is to combine what is known about synthesis and enzymatic degradation of the components of fibers and ground substance. Common pathological phenomena like chronic inflammation of immune reactions can be either the result of the cause of disturbances in the sensitive balance of connective tissue metabolism. Nowadays con­ nective tissues are less and less regarded as brady trophic tissue but rather as a stimulating and many-sided problem of research. Before we can understand the pathogenesis of the connective tissue diseases that result in the destructive processes mentioned above, basic research will be necessary. This research will be furthered by a constant exchange of information and the results of· observations. To promote this exchange of information between scientists, symposia on connective tissue research are organized at regular intervals.