Over the last few years, we have witnessed tremendous progress in the field of eicosanoids and their therapeutic applications. Receptor an­ tagonists for leukotrienes have been tested as anti-inflammatories and are on the market as a treatment for asthma. Receptor agonists for pro­ stacyclin are being tested for the treatment of peripheral vascular dis­ ease, and selective inhibitors of cyclooxygenase type II were just ap­ proved for the treatment of rheumatoid arthritis. All these developments are the culmination of many years and man-hours of careful research. The field has now entered an upswing that will result in novel therapeutic applications within the next 10 years. New molecules and me­ diators have been identified, new enzymes and pathways elucidated and new therapeutic approaches have emerged. The concept of ei­ cosanoids as "pro-inflammatory" molecules is being challenged, and their role as regulators is increasingly recognized. In fact, some of these molecules may be important endogenous anti-inflammatory agents.