For small and medium sized economies that are very open to trade and capital
flows, changes in the value of the exchange rate can have a significant influence on
inflation and the real economy. The choice of the exchange rate regime as well as
appropriate policies required to back it up are, therefore, central to the successful pursuit
of macroeconomic stability and the achievement of sustainable growth. In the aftermath
of the Asian crisis, there was initially a general shift away from intermediate exchange rate
regimes in favor of ‘corner solutions’—a clean float on the one hand, or a rigid peg (such
as a currency board) on the other. That said, many countries—including Thailand—have
moved towards managed floating which involves occasional intervention by the central
bank in the foreign exchange market in response to specific shocks or concerns. In this
setting, a set of principles and guidelines is needed to formulate the decision of when and
how much to intervene. Effective exchange rates are part of a set of tools that can be used
in this respect.