Boethius's De Consolatione Philosophiae was among the most persistent and extensive influences on Chaucer's writing. Its ideas appear in various works, including the Knight's Tale and Troilus and Criseyde, while the so-called Boethian balades offer poetic renditions of small sections of the Consolation. Around 1380 Chaucer translated the whole of the Consolation into English, drawing not only on the Latin Vulgate Consolatio but also on Jean de Meun's French translation (Li Livres de confort de philosophie) and on Nicholas Trevet's Latin commentary on the Consolatio. Sources of the Boece will be particularly valuable for Chaucer studies, for it makes available for the first time copies of all Chaucer's sources for his translation: newly edited, complete, facing-page texts of the Vulgate Consolatio and Meun's translation, along with relevant extracts from the commentaries of Nicholas Trevet and Remigius of Auxerre and collations from the larger Latin and French traditions. The edition thus enables detailed, comparative studies of Chaucer's use of his sources and provides additional material for assessing his understanding of Boethius's ideas and how they figure in his other compositions. More generally, the very format of the edition will facilitate the study of translation in the Middle Ages, when writers worked not from standardized editions like the ones modern scholars consult but from variable and sometimes conflicting traditions. Chaucer's procedures provide insights into medieval notions of textuality and vernacular authorship, issues that are perennial scholarly concerns.