Schulz/Leporello The essays in this international overview of the phenomenon of folded books cover 600 years of western book history, ranging from mediaeval folded books and early modern harlequinades, through folded leaves in bound books, to the leporellos, folded panoramas and livres-accordéon which flourished in the 19th century. In the 20th century folded books enjoyed an international renaissance both in experimental literature and in the context of Artists’ Books. The material expansion of the bookblock is far more than just a surprising effect: it allows for other forms of producing content than those available in a bound book, and thus for different reading experiences. Books that can be unfolded transform themselves before the eyes of their viewers. Folding is a rich and complex aesthetic strategy, especially in the context of book history. The richly-illustrated stories of folded books collected here constitute a hitherto undiscovered book-historical treasure.