Edward Gordon Duff (1863-1924) was a bibliographer and librarian with a particular interest in early printed books. He was librarian of the John Rylands Library, Manchester, from 1893 to 1900, and Sandars Reader in Bibliography at Cambridge in 1899, 1904 and 1911. Alongside research and writing he also did freelance cataloguing. Duff s work set new standards of accuracy in bibliography, which he considered a science. This 1905 work, published by the Bibliographical Society, contains short biographies of all the known participants in the English book trade from 1457 to 1557, whether printers, bookbinders, or stationers, organised in alphabetical sequence. It reveals that during the fifteenth century the majority of printers working in England were foreigners, but after 1500 English representation increased. Although Duff s list has been supplemented by more recent research, it remains a valuable work of reference, and sheds considerable light on the early English book trade.