Mainstream economics fails to grasp the specific nature of money. It is seen either as a #neutral veil# over the operation of the #real# economy or alternatively as a #thing# # a special commodity. In this important new book, Geoffrey Ingham draws on neglected traditions in the social sciences to develop a theory of the #social relation# of money. Money consists in socially and politically constructed #promises to pay#. This approach is then applied to a range of important historical and analytical questions. The historical origins of money, the #cashless# monetary systems of the ancient Near Eastern empires, the pre-capitalist coinage systems of Greece and Rome, and the emergence of capitalist credit-money are all given new interpretations. Capitalism#s distinctiveness is to befound in the social structure # comprising complex linkages between firms, banks and states # by which private debts are routinely #monetized#. Monetary disorders # inflation, deflation, collapse of currencies # are the result of disruptions of, or the inability to sustain, these credit-debt relations. Finally, this theory of money#s #nature# is used to clarify confusions in the recent debates on the emergence of new #forms# and #spaces# of money # global electronic money, local exchange trading schemes, the euro.