Commercial Perspective : Trade between two business firms located in different countries begins with the conclusion of an export contract. Under the contract, the duty of the exporter is to ship the contracted goods in the agreed form (e.g., packing) and by agreed mode of transport as well as according to agreed time schedule. On the other hand, it is the duty of the importer to remit sale value to the exporter according to agreed terms of payment. In this process of physical movement of goods from the exporter to the importer and remittance of sale value in the reverse order, neither the exporter nor the importer is personally and physically involved. Instead goods and handed over to a shipping company or an airline which issues a receipt for these goods.

Further, since goods in transit may be damaged or lost due to some accident, the exporter may be required to get an insurance policy. While these two documents will protect the interrupts of the importer, the exporter will ensure that these documents are not in the possession of he importer unless he has either paid for the goods or he has made a promise to make payment at a later date. For this purpose, physical possession of the goods will be linked with the acceptance of a payment document by the importer. In actual practice, a set of documents given proof of shipment and cargo insurance coverage along with a bill for payment is sent by the exporter to the importer through the banking channel. This set of documents symbolises ownership in goods. This will be handed over to the importer by the bank in his country which he has received it from the bank in the exporting country only when he has honoured the bill. In other words, the importer will get delivery of the goods from the carrier on the basis of the transport document which is obtained through the bank, after he has complied with the agreed tern of payment.