He has published extensively on aspects of provenance, private libraries and bookbinding and his projects currently in hand include a directory of book ownership in 17th-century England. He teaches regularly on the Rare Book Schools in London and Charlottesville. He is a Past President of the Bibliographical Society and is appointed Lyell Reader in Bibliography at Oxford for 2017-18.
His English Bookbinding Styles 1450-1800 and other publications on binding and book ownership are well known as standard reference works in their fields. He has taught courses on bookbinding and book provenance for many years at the Rare Book Schools in London, Virginia and Sydney and is a regular tutor on the MA History of the Book programme in the Institute of English Studies.