The main subjects of enquiry in this volume focus upon the major areas in which the honorand, Gordon Leff, has himself made fundamental contributions. Among the topics discussed are learned and popular heresy (Cathars, Wyclif, Lollardy, and the concept of heresy itself); the history of medieval universities and thought (including the religious at Paris and Cambridge, Ockham, and Paris theologians' views on the Jews); and early modern views of the crusades.The book is completed with a bibliography of works by Gordon Leff. Dr PETER BILLER is Senior Lecturer at the University of York; Professor BARRIE DOBSONis at Christ's College, Cambridge.