This book shows that the use of money transforms a market economy into a payment society where production and employment are subordinated to the logic of asset markets. Monetary policy emerged out of private banking business and was always exposed to the risk of losing credibility and reputation. The stability of key currency systems was based on different policy preferences. A simple game-theoretic macro model explains the working and the downfall of the gold standard, Bretton Woods and the European Monetary System. It is shown that waning willingness to accept foreign leadership in monetary policy affairs propelled the creation of the euro.