Error notes continue to carve an ever larger niche in paper money collecting. This revised reference offers collectors a comprehensive catalog of known U.S. paper money errors and includes examples of each error and detailed information on paper money printing. Updated values are provided in up to three conditions. Errors are thoroughly described and depicted, including overprint, folding and first and second printing errors. Historical photographs from the Bureau of Engraving and Printing reveal rarely seen images of U.S. paper money workers inside the printing office.