Pre-Shipment Inspection (PSI) is a random inspection that includes a detailed inspection of the finished product prior to shipment.
It generally takes place in either manufacturer, stocker promises or custom. Samples randomly selected according to statistical sampling procedures specified in ISO 2859-1 or agreed with the customer.
Inspection criteria include type identification, product suitability, safety, functionality, labeling and safety recommendations, quality (consistent processing), quantity, packaging, integrity of the product. units and agreed specifications.

One of the main concerns of merchants has always been to ensure the accuracy of the shipment sent by the seller. Probable quantitative and qualitative errors in prepared shipments are trade risks.