Ibn Bagga's commentary on Aristotle's On Generation and Corruption (Kitab al-Kawn wa-l-fasad, Latin De generatione et corruptione) is one of the first commentaries to elaborate on the essential aspect of Aristotle's text, that is, the analysis of change ( , tagayyur). The commentary's extant parts comprise a consecutive exposition of the contents of Aristotle's work. However, the commentary may be read more as an introduction or a guide to the topic of generation than as a substitution for the original, as the paraphrases by Averroes seem to have become in the later tradition. The present study provides a new critical edition of the Arabic text and, for the first time, an English translation and a study of the structure of the commentary on the basis of the only two known manuscripts.