The Montpellier Codex is the largest and most sumptuous extant manuscript of thirteenth-century polyphonic music. The works it contains represent the music of the entire thirteenth century, and perhaps that of the late twelfth century as well. Inspired by Yvonne Rokseth’s earlier transcriptions, the present edition draws on nearly four decades of subsequent research to offer improved readings of many motets, and comprehensive collation and analysis of all concordances. The musical transcriptions...