This collection examines the significance of the ways in which writing was used in the Celtic countries between c.400 and c.1500. It is concerned with the amount and types of material committed to writing as well as with the social groups that promoted the use of literacy and had access to its products. Presenting the fruits of much new research, the book is intended as a contribution to the study both of medieval literacy generally and of the history and cultures of Ireland, Scotland, Wales and Brittany in the Middle Ages.