【正文】 tical forces have affected past choices of exchange rate systems? Who are the winners and who are the losers from changes in the system, or the continued operation of either system? (A rule of thumb: if you don’t know, then you’re probably not one of the big winners.) Are the main forces benevolent advocates of some “mon good,” or more 8 subtle proponents of special interests? Discussion of exchange rate systems has tended to ignore these issues, and focused mainly on costs and benefits for the mythical “representative individual.” Yet few changes in government policy, even in (or particularly in) subtle aspects of moary and financial policies of governments, fail to involve special interests hiding beneath the veneer. Currencies are naturally tied to central banks (or currency boards). A change to a mon currency, such as the Euro, requires a change in institutions for moary policy. And other institutional changes that affect regulation and oversight of financial markets and institutions, tax policies, regulatory policies, and government spending are likely to acpany that change in moary institutions. The consequences of these institutional changes may be farreaching, and might easily dominate other costs and benefits attributable to the difference between a mon currency and many currencies. This issue generalizes beyond a system of mon currencies, to a system of pegged exchange rates among nations with separate central banks. Policies of pegging exchange rates can create problems that lead to formation and involvement of institutions (such as the International Moary Fund) that play various roles in “managing” the “international moary system.” Those changes in institutions involve changes in political pressures and other kinds of policies. Of course, these institutional changes may have benefits rather than costs. But when political forces start clamoring for a change in institutions, it is time for wise men to bolt their doors and close their shutters, before someone from the government arrives on the front stoop. The Future One view of the future asserts that the dollarEuro exchange rate will bee the key exchange rate, leading to pressure to stabilize it, and 9 that Japan will want to keep the value of the Yen closely linked to both those currencies. Robert Mundell (1999: 444) believes that “by 2020 we will be back to a world where we get more fixed exchange rates, and the International Moary Fund will be dragged back to its original function.” An alternative view is not simply less Eurocentric (noting the increased role of Asian nations in addition to Japan in the future world economy), but also less governmentcentric. While some political forces will seek stabilization of the exchange rate between the dollar and the Euro, other sorts of political pressures will emerge for various national policies that are inconsistent with such stabilization. Meanwhile, technological developments will result in increased sophistication of financial and payment systems that makes the issues increasingly less important. Eventually, people may be able to choose both the units of account and the medium of exchange that they employ for their own transactions, and they may even employ multiple units of account— and multiple media of exchange (which are likely to be increasingly electronic and increasingly provided by private firms) in their various trades (see Dorn 1997). Consequently, people may want petition among units of account so that they can freely choose the one that suits them best. It seems unlikely that fixing exchange rates— or adopting mon currencies— will help to create a money that people will choose to adopt as either a unit of account or a medium of exchange. On the contrary, increasing private entry into this market may occur despite difficulties of collecting revenues on a “public good” like a unit of account (although technology may take care of that, . with small royalties for the verified use of such a unit), and these peting units will likely involve marketdetermined relative prices (floating exchange rates). Fifty years from now, governmentprovided moneys are unlikely to play a major role in most ordinary peoples’ lives, unless governments pete 10 aggressively against private petitors, and this petition is likely to entail floating exchange rates (variable relative prices) among these peting modities. Conclusion Where does this leave current policy? Economists lack strong evidence on how exchange rate systems affect the economic variables that people care about, such as longrun growth, avoidance of dislocations from business cycles, and so on. They also lack theory and evidence on how the choice of system affects the political forces that operate on moary policies of central banks, and on their policies toward regulation, oversight, and bailouts of financial institut