The present article analyses and makes available one of the earliest known texts on book preservation. The text in manuscript The Hague, KB 133 F 2 dates back to 1527 and contains eight guidelines on how to preserve books. These guidelines give us a unique insight into the way people in the later Middle Ages thought about handling books and the risks involved. An analysis of the contents of these age-old guidelines in light of modern book preservation indicates that the causes of deterioration and degradation identified back then still hold true today. In addition, this set of medieval instructions can be seen as one of the earliest foundations of our present-day regulations on access, handling and storage.