This is the second of a projected series of four volumes describing manuscripts and fragments in British libraries containing commentaries on the Latin Aristotle. This volume covers the University Library, the Fitzwilliam Museum, and the college libraries of the University of Cambridge. It lists 152 items (including a portfolio of fragments from several original books), dating from the tenth century until c. 1500. While a few of these manuscripts came to Cambridge after the Reformation, the majority were already in use in the medieval University. Not many have been adequately described before, while most of the anonymous commentaries have not been listed anywhere. Four indexes are provided to facilitate searching the main text. Rodney M. Thomson is Emeritus Professor of Medieval History at the University of Tasmania and Honorary Research Fellow in its School of History & Classics. He has published widely on books, libraries and learning in western Europe between the ninth and sixteenth centuries.