reduction in the exchange value of a country's monetary (money) unit in terms of gold, silver, or foreign monetary units. Devaluation is employed to eliminate persistent balance-of-payments (balance of payments) deficits. For example, a devaluation of currency will decrease prices of the home country's exports that are purchased in the import country's currency. While making the exported goods cheaper for other countries, devaluation also increases the prices of imports purchased in the home country. If the demand for both exports and imports is relatively elastic (that is, the quantity purchased is highly responsive to changes in price), the country's income from exports will rise, and its expenditure for imports will fall. Thus, its trade will be more in balance and its balance of payments improved. Devaluation will not be effective if the balance-of-payments disequilibrium is a result of basic structural flaws in a country's economy.

In contrast to devaluation, revaluation involves an increase in the exchange value of a country's monetary unit in terms of gold, silver, or foreign monetary units. It may be undertaken when a country's currency has been undervalued in comparison with others, causing persistent balance-of-payments surpluses. (See also exchange control.)