Xylitol, a polyol with growing market as a sweetener; can be produced by either chemical or biotechnological methods. The chemical properties of xylitol relevant; to its food applications are summarized. The applicable production technologies (extraction from vegetables and fruits, chemical synthesis and biotechnological processes based on the utilization of bacteria, fungi or yeast) are described. Special attention is paid to the fundamentals of xylose metabolism by yeast, since this is a key factor affecting the feasibility of the most promising biotechnological methods for xylitol production. Other related technologies, involving the utilization of enzymes, combinations of enzymes and microorganisms or mixed cultures of microorganisms, are also described.