The texts edited in this volume are Ælfric's vernacular versions of two highly influential early medieval ethical treatises. The first, De duodecim abusiuis, is his Old English version of a seventh-century Hiberno-Latin tract dealing with the twelve abuses of the world. The second, De octo uitiis et de duodecim abusiuis, is a composite text; it combines a treatment of the eight vices and the complementary eight virtues, also found as the last part of Ælfric's Lives of Saints XVI, with the twelve abuses. The main source for the virtues and vices is Alcuin's ninth-century I>De uirtutibus et uitiis. Both texts were composed in Ælfric's hallmark rhythmical, alliterative prose. This new edition provides, for the first time, critical editions of both texts, with a facing translation, presented with full apparatus; it also includes an extensive discussion of the sources and how they are treated. Mary Clayton is Professor of Old and Middle English, University College Dublin.