James Madison’s Notes on the 1787 Constitutional Convention have acquired nearly unquestioned authority as the description of the U.S. Constitution’s creation. No document provides a more complete record of the deliberations in Philadelphia. But how reliable is this account? In an unprecedented investigation Bilder reveals that Madison revised the Notes to a far greater extent than previously recognized. Madison’s Hand offers a biography of a document that, over two centuries, developed a life and character all its own.