Introduction / L. Randall Wray and Stephanie Bell -- What is money? / A. Mitchell Innes -- The credit theory of money / A. Mitchell Innes -- The social origins of money : the case of Egypt / John F. Henry -- The archaeology of money : debt versus barter theories of money's origins / Michael Hudson -- The primacy of trade debts in the development of money / Geoffrey W. Gardiner -- The emergence of capitalist credit money / Geoffrey Ingham -- Conclusion : the credit money and state money approaches / L. Randall Wray.