During the latter half of the 20th century, geometry largely fell out of favor within the mathematical community. As Canadian journalist Roberts so well describes in her first book, Donald Coxeter (1907-2003), a University of Toronto mathematician, almost singlehandedly preserved and advanced the discipline through hard work and acute insights. His impact has been felt in a wide variety of fields and acknowledged by the likes of Buckminster Fuller and M.C. Escher. Coxeter also helped transform mathematics education to bring geometry back into the mainstream. This change is critical because, as Roberts explains, a robust understanding of geometry is essential for progress in disciplines from crystallography to cosmology, and from video graphics to immunology. Given Coxeter’s long life and career, his biography, in large part, tells the story of mathematics in the 20th century as well as a human portrait of a man who-despite his royal title-was a "humble, hands-on geometer." Roberts, who won a National Magazine Award for a Toronto Life profile of Coxeter, puts most of the technical material in appendixes, so the text is readily accessible to a general audience. 70 b&w photos and diagrams.