Between the 14th and 16th centuries a little-known book format, now called the girdle book, was used throughout various European countries. 'The girdle book' is distinguished by a cover that extends beyond the limits of the book itself and may end in a knot, hook or ring, or may be left ungathered. By this extension the book was hung from the belt with its head down, so when swung up it could be read without detaching it from the belt.0Today there are only twenty-six known examples identified and documented in collections worldwide. In 'The Medieval Girdle Book', the author provides a comprehensive look at these extremely rare books. A study of this scope, which contributes significantly to the information available has been lacking until now and makes this the first thorough treatment of all so far known girdle books. 0The author has examined each book in detail, documented its historical context, provenance, owner(s) or institutions associated with it, and described each from the bookbinder's perspective, including the materials and processes of their construction. Contrary to previous assumptions that only clerics and the religious used girdle books, 'The Medieval Girdle Book' shows they also contain legal, medical, and philosophical contents.