Abstract: A method and apparatus are provided relating to a secure bag assembly to secure cash in transit (“CIT”). In some implementations, the secure bag assembly is installed in a lockable, removable cassette that is fitted to a bill validator. The cassette and bill validator can be installed in an enclosure like those found in retail kiosks, self-checkout terminals, retail safes or gaming machines. In such an implementation, bank notes are deposited in the bill validator and once identified and validated, are securely stacked in the bag assembly within the cassette. The bag assembly can be used for capacities of one banknote up to the maximum capacity allowed by the cassette. The bag assembly is secured in place when installed and is sealed automatically upon removal from the cassette.