The idea of a series of volumes to be known as The Cambridge Translations of Medieval Philosophical Texts originated in the Cambridge University Press almost as soon as work on The Cambridge History of Later Medieval Philosophy had begun. The first volume in the series, Logic and the Philosophy of Language, edited by Norman Kretzmann and Eleonore Stump, appeared in 1988. Work on the present volume began in 1991 with the selection of texts to be translated and the gathering of a team to do the translating. We are now happy to present a body of texts in moral philosophy which we have come to appreciate increasingly while working with them. A. S. McGrade, who is primarily responsible for Translations 1–2 and 13–14 and for editing the volume as a whole, was able to devote full time to the project in early 1991, thanks to a sabbatical leave from teaching granted by the University of Connecticut and a Visiting Fellowship from Clare Hall, Cambridge, and in 1994–95, thanks to a grant from the Translations Program of The National Endowment for the Humanities and the further hospitality of Clare Hall. Supplementary grants from the University of Connecticut Research Foundation and the encouragement of its director, Thomas G. Giolas, have been a great help to him. He is also grateful to the staffs of libraries at the University of Cambridge; the Episcopal Divinity School in Cambridge, Massachusetts; Harvard University; Yale University; the University of Connecticut; and St. John's College and Merton College, Oxford.