A system for controlling currency exchange and merchandise sales on commercial airline flights includes a point-of-sale (POS) computer for receiving currency and merchandise inventory information preflight and for recording transactions in-flight. Data is exchanged between the POS computer and a cash/currency processing computer (CPC) for reconciling preflight and post-flight inventories and for generating reports for use by the airlines, merchandise vendors and currency exchange service providers. A control method includes the steps of determining currency and merchandise inventories preflight, recording transactions in-flight and reconciling and reporting transactions post-flight.