Julian Schwinger is an unsung hero of twentieth century theoretical physics, whose impact on the subject is as deep and wide-ranging as that of his more charismatic contemporary Feynman. His abilities as a teacher were also legendary; to date four of his former students have won a Nobel Prize. Since his death in 1994 a detailed technical biography, several compendia of his published works, and texts based on his lecture courses have appeared, and provide him with a fitting memorial, albeit one accessible only to his fellow professional scientists. This book is rather different. Based on a course devised for the Open University, it provides the layman with an excellent account of the theories of special and general relativity. Well laid out, lavishly illustrated and presented in clear and non-technical terms, Einstein's Legacy (whose author was criticised unfairly by Oppenheimer for an expositional style that strove to demonstrate not how a problem might be solved, but that only he could solve it) is a model of clarity and is "as simple as possible, but not more so". Schwinger contributed a great deal to the unification of quantum mechanics and special relativity, and thought deeply about the still to be achieved reconciliation of QM and the general theory. Here the non-professional reader can share the understanding that emerged from Schwinger's life's work at the frontiers of physics in a book that is a celebration of both Einstein's revolutionary insights and a man who did as much as any of his contemporaries to develop and apply them.