Yeasts are not only essential for the production of bread, beer and wine, but also play a major role in many more modern industrial processes, such as the production of enzymes, pigments, antioxidants etc. Moreover, many yeasts are important as human pathogens, or as spoilage organisms in the food industry. This CD-ROM, produced by leading experts in the field, offers a multi-disciplinary approach to the identification of all 719 species of this fascinating group of micro-organisms. It not only contains descriptions and photographs of the morphology, but also a complete set of physiological data as well as ribosomal DNA sequences. All these data can be used for an interactive identification of unknown yeast isolates. Moreover, the system contains the identification software for ALLEV, at this moment the most flexible identification system based on automated reading of microtitre plates.