This thesis aims to identify the major characteristics of the contemporary book cover, and to show how these characteristics have grown out of the very different forms which book covers took before the nineteenth century. The evolution of the book cover is discussed with reference to various threads in the history of publishing and bookselling. The most important of these are: developments in the technology of book binding; the emergence of professional graphic design; and the restructuring of retail trade. The confluence of historical threads has given the cover a crucial role in contemporary international book trade, stimulating visual processes of recognition and identification that are central to contemporary methods of bookselling.