This volume provides a wide-ranging account of the development and importance of private libraries and book ownership through the seventeenth century, based upon many kinds of evidence, including examination of thousands of books, and a list of over 1,300 known owners from diverse backgrounds. It considers questions of evolution, contents and size, and motives for book ownership, during a century when growing markets for both new and second-hand books meant that books would be found, in varying numbers, in the homes of all kinds of people from the humble to the wealthy. Book ownership by women, and by non-professional households, is explicitly explored. Other topics include the balance of motivation between books for use, or for display; the relationship between libraries and museums; and cultures of collecting. While presenting a wealth of information in this field, conveniently brought together, this volume also advances methodologies for book history, and makes extensive use of material evidence such as bookbindings. It challenges received wisdom around priorities for studying private libraries, and the terminology which is appropriate to use. In addition, the list of owners, detailed in the Appendix, make this book a work of permanent reference, alongside its value in advancing book history.