Keynes always intended to write 'footnotes' to his masterwork The General Theory, which would take account of the criticisms made of it and allow him to develop and refine his ideas further. However, a number of factors combined to prevent him from doing so before his death in 1946. A wide range of Keynes scholars - including James Tobin, Paul Davidson and Lord Skidelsky - have written here the 'footnotes' that Keynes never did.