An arrangement in which two parties exchange specific amounts of different currencies initially, and a series of interest payments on the initial cash flows are exchanged. Often, one party will pay a fixed interest rate, while another will pay a floating exchange rate (though there may also be fixed-fixed and floating-floating arrangements). At the maturity of the swap, the principal amounts are exchanged back. Unlike an interest rate swap, the principal and interest are both exchanged in full in a currency swap.