This volume scopes several aspects of non-conventional yeast research prepared by the leading specialists in the field. An introduction on taxonomy and systematics enhances the reader's knowledge on yeasts beyond established ones such as Saccharomyces cerevisiae. Biotechnological approaches that involve fungal utilization of unusual substrates, production of biofuels and useful chemicals as citric acid, glutathione or erythritol are discussed. Further, strategies for metabolic engineering based on knowledge on regulation of gene expression as well as sensing and signaling pathways are presented. The book targets researchers and advanced students working in Microbiology, Microbial Biotechnology and Biochemistry.