On January 1, 1999, the euro was launched with eleven members and it instantly became the second most important currency in the world. It may prove to be the most important event in the history of the international monetary system since the dollar took over from sterling the role of dominant international currency. For the time being the mainstream of the world economy will be characterized by a tripolarism based on the dollar, euro and yen The new situation raises some old questions: Is the currency configuration of the world economy optimal? How many currencies does the world need? Which countries belong in a currency area? What is the optimum currency area? This paper will discuss the currency composition of the world economy today. It will discuss the prospects for expansion of the major currency areas and the problems arising from the volatility of exchange rates between them. It will argue that a restoration of a system of fixed exchange rates would have to begin with stabilization of the exchange rates between the dollar, euro and yen, and that a step in the right direction would be to evolve policies that provide for intervention in the foreign exchange market.
