Local levels of 5-lipoxygenase pathway products are the net result of stimulus-induced local synthesis and subsequent degradation. These events are regulated by the interaction of leucocytes with stromal cells and locally produced cytokines and growth factors, and may be modulated by the fatty acid composition of cellular membrane phospholipids and extracellular fluid unesterified fatty acids. A more comprehensive understanding of the regulation and modulation of the 5-lipoxygenase pathway may result in more effective management of inflammatory and immune disorders.