The problem of optimal exchange intervention is approached using the techniques derived in the "targets, instruments, and indicators" literature. The optimal exchange-rate policy is one of permitting the appropriate degree of exchange-rate flexibility rather than one of complete fixity or complete flexibility of the exchange rate. Although the problem of the optimal exchange-rate regime has been analyzed in these terms before, criteria previously employed, emphasizing the geographical or functional location of disturbances, are seen to be inappropriate for a portfolio balance model with some degree of capital mobility.

The problem of optimal exchange intervention is approached using the techniques derived in the "targets, instruments, and indicators" literature. The optimal exchange-rate policy is one of permitting the appropriate degree of exchange-rate flexibility rather than one of complete fixity or complete flexibility of the exchange rate. Although the problem of the optimal exchange-rate regime has been analyzed in these terms before, criteria previously employed, emphasizing the geographical or functional location of disturbances, are seen to be inappropriate for a portfolio balance model with some degree of capital mobility.