Book excerpt: Key Chiral Auxiliary Applications, Second Edition is a detailed compilation of chiral auxiliary applications organized by type of transformation. Continuing from the most important and relevant auxiliaries described in its predecessor, the three-volume set Compendium of Chiral Auxiliary Applications (2001), as well as advances in the field, the book provides a vital and timely resource for chemists in the field. Each reaction class includes a series of tables and graphical abstracts of real reactions from the literature and patents to enable easy review and comparison of results. This anticipated edition is based on a screening of nearly 40,000 auxiliary reaction applications, with details supplied for the more than 13,000 selected representative entries: synthetic route, reagents, yields, diastereomeric/enantiomeric excesses, and characterization data. Updated and streamlined with more than 60% new material, Key Chiral Auxiliary Applications provides valuable guidance and reliable content for selecting the best auxiliary for a specific asymmetric synthetic transformation. Provides a comprehensive compilation based on nearly 40,000 diverse applications of chiral auxiliaries for selecting the best synthetic route to optically pure compounds Contains over 60% new material with 13,000+ auxiliary applications categorized by reaction type, with reaction details and chemical and optical yields in one unique resource