For rare-books librarian Matthew Battles, libraries represent a compelling paradox. On the one hand, they exist to collect and preserve knowledge. On the other hand, they have been used to control, restrict, and sometimes obliterate knowledge. Battles takes us on a spirited foray from classical scriptoria to medieval monasteries, from the Vatican to the British Library, from socialist reading rooms and rural home libraries to the Information Age. At the same time, he gives due attention to both what has been found and what has been lost—from the clay tablets of ancient Mesopotamia to the storied Alexandrian libraries in Egypt, from the burned scrolls of ancient China to the book pyres of the Hitler Youth. This history speaks volumes about the care of the written word.