This is an excerpt from the 4-volume dictionary of economics, a reference book which aims to define the subject of economics today. 1300 subject entries in the complete work cover the broad themes of economic theory. This extract concentrates on money, a subject that has been at the centre of economic debate over the centuries, providing a striking illustration of the interaction between practical policies and the development of theory. This volume follows the course of that debate from the Bullionist Controversy of the Napoleonic period to the perennial arguments over the gold standard, to the disputes betwen Keynesians, monetarists and "new classical macroeconomists" tracing the evolution of theory over nearly 200 years.