The study of manuscripts is one of the most active areas of current research in medieval studies: manuscripts are the basic primary material evidence for literary scholars, historians and art-historians alike, and there has been an explosion of interest over the past twenty or twenty-five years. Manuscript study has developed enormously: codices are no longer treated as inert witnesses to a culture whose character has already been determined by the modern scholar, but are active participants in a process of exploration and discovery. All aspects of the manuscript's physical existence are relevant to such an enquiry, not just the texts it contains, but the materials, the choice and arrangement of contents, the lay-out and format of the page, the choice of script, the hierarchy of decoration, the illustration, the use of marginal annotation and glossing. Even after a manuscript has been ‘published’, it remains an active witness to the culture of its reception, in the scope it offers for readers' marginal and other comments.

I believed all this twenty years ago, when during the early 1980s I organised a series of biennial conferences at the University of York on late medieval English manuscript studies. Two books of essays collected from the papers given at those conferences were subsequently published: Manuscripts and Readers in Fifteenth-Century England: The Literary Implications of Manuscript Study, Essays from the 1981 Conference at the University of York (Cambridge: D. S. Brewer, 1983), and Manuscripts and Texts: Editorial Problems in Later Middle English Literature, Essays from the 1985 Conference at the University of York (Cambridge: D. S. Brewer, 1987).