Wulfstan of York was by any measure a central figure in late Anglo-Saxon England. Clues to Wulfstan's range of reading can be gleaned from several different kinds of evidence, namely those books he annotated, those books he compiled, and those he echoed in his own works. Manuscripts, whether they were produced for or annotated by Wulfstan, or were compiled under his supervision, or seem to reflect earlier such compilations, are naturally of primary importance in attempting to reconstruct Wulfstan's library. No fewer than eighteen such manuscripts survive which provide an invaluable witness to what Wulfstan read and chose to be transmitted. Wulfstan's habits of reading and annotation contain a range of material, from collections of canon law, penitential texts, liturgical material, sermons and homilies and letters, together with the occasional poem. Reorganisation, repetition and recycling of the material at his disposal seem to have been the hallmark of all Wulfstan's work, as exemplified by his composition: Sermo Lupi ad Anglos.