Written for his brother Benedictine monks around 1077, Anselm's Proslogion is perhaps the best-known partially-read book of the Middle Ages. Many readers are familiar only with Anselm's well-known argument for God's existence in Chapters 2-4, which is often called the "ontological argument," a misleading appellation coined centuries later by Immanuel Kant. In this argument Anselm begins with the thought of "something than which nothing greater is able to be thought," and subsequently he leads the reader to see that such a reality necessarily exists and cannot be thought not to be. This argument - which is, to be sure, crucial to the work constitutes - but a small portion of the whole. Preceding it is a profound but oft-overlooked opening chapter in which Anselm contemplates his all-too-human condition and disposes the reader to receive aptly his argument for God's existence in the next three chapters. And following this argument are 20 chapters in which Anselm artfully unfolds the depth and breadth of God's true existence as that than which nothing greater is able to be thought, showing God to be (among other things) able-to-sense, pity-hearted, just, good, and uncircumscribed. Indeed, if the reader is willing to give himself over to the work as whole, he will be compelled, under Anselm's deft guidance, to "endeavor to straighten up his mind toward contemplating God," which is how Anselm describes his own role in the work in his prefatory remarks. This edition provides a faithful yet readable English rendering of the whole Proslogion, the objections raised to Anselm's argument by his contemporary Gaunilo, and Anselm's replies to those objections. (After responding to Gaunilo, Anselm himself requested that these objections and replies be included in subsequent editions of the Proslogion.) This edition also includes an introduction that contextualizes the Proslogion within the monastic, pre-Scholastic age in which it first made its appearance. In addition, by means of notes and commentary, this edition articulates how to contextualize Anselm's famous argument in the Proslogion as a whole and in light of his replies to Gaunilo, how to appreciate the artistry whereby Anselm knit the Proslogion together into a coherent and concise unity, and how the work may be taught effectively to interested students. These features set this affordable English edition of the Proslogion apart from those currently available, which too often fail to capture accurately the beauty of Anselm's prose, which often treat the work through the lens of either later Scholasticism or contemporary analytic philosophy of religion, and which take little note of the craftsmanship whereby Anselm constructed this masterfully integrated work that is remembered too often for too few of its 24 chapters. Matthew Walz has taught in the interdisciplinary program at Thomas Aquinas College in California, and since 2008 he has been a professor in the Philosophy Department of the University of Dallas.