Between 1975 and 2000 de Hamel worked for Sotheby’s in its Western Manuscripts Department.[7] He was elected as the Donnelley Fellow Librarian of Corpus Christi College, Cambridge in 2000,[2] and elected a member of the Roxburghe Club the following year.[8] De Hamel delivered the 2009 Lyell Lectures at Oxford University on the subject of "Fragments in Book Bindings".[9] In 2017, his then-newly-published Meetings with Remarkable Manuscripts was shortlisted for Waterstones Book of the Year 2016, and won both the £40,000 Wolfson History Prize and the Duff Cooper Prize.[10]