This is the first volume exclusively devoted to the Expositio by Berthold of Moosburg (c.1295-c.1361) on Proclus’ Elements of Theology. The breadth of its vision surpasses every other known commentary on the Elements of Theology, for it seeks to present a coherent account of the Platonic tradition as such (unified through the concord of Proclus and Dionysius) and at the same time to consolidate and transform a legacy of metaphysics developed in the German-speaking lands by Peripatetic authors (like Albert the Great, Ulrich of Strassburg, and Dietrich of Freiberg). This volume aims to provide a basis for further research and discussion of this unduly overlooked commentary, whose historical-philosophical importance as an attempt to refound Western metaphysics is beginning to be recognized. The publication of this volume has received the generous support of the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme through the ERC Consolidator Grant NeoplAT: A Comparative Analysis of the Middle East, Byzantium and the Latin West (9th-16th Centuries), grant agreement No 771640 (www.neoplat.eu). “[...] the volume displays various aspects of the richness hidden in this Commentary on Proclus: the contributions mentioned here are merely representative of such richness. Nonetheless, a desideratum of the research on Berthold remains a closer analysis of his polemical relations with his still unknown adversaries.” -Giuseppe Thomas Vitale, Thomas-Institut der Universität zu Köln, Recherches de Théologie et Philosophie médiévales 89.2