Currency boards were once common in colonial regimes but are now only found in small countries like Singapore, Brunei, and Hong Kong. In this system, the board guarantees to exchange domestic currency for foreign reserve currency at a 1:1 ratio. This means there is no extra money printed without backing. Banks usually handle the currency exchange, with a spread in rates to cover costs. However, this system only applies to physical currency, not bank deposits or other assets. If you want to convert a bank deposit to foreign currency, you first need to convert it to domestic currency.