An easy source of unusual monosaccharides such as the 6-deoxyhexose, L-fucose are certain microbial extracellular polysaccharides (EPS), best known for their thickening, gelling or emulsifying properties. L-Fucose and L-fucose containing oligosaccharides have potential application in the medical ®eld in preventing tumour cell colonisation of the lung (anticancer effect), in controlling the formation of white blood cells (anti-in¯ammatory effect), in the treatment of rheumatoid arthritis, in the synthesis of antigens for antibody production (rational immunisation) and in cosmeceuticals as skin moisturing agent. L-Fucose production via chemical synthesis is laborious and suffers from low yield, while direct extraction from brown algae is costly and subject to seasonal variations in supply volume and quality. Enzymatic synthesis is currently under investigation. Chemical or enzymatic hydrolysis of L-fucose-rich microbial EPS opens up a new route towards ef®cient L-fucose production. This review deals with the properties, occurrence, physiological roles, chemical, enzymatic and microbial production of L-fucose.