Rules of origin are the criteria needed to determine the national source of a product. Their importance is derived from the fact that duties and restrictions in several cases depend upon the source of imports. Rules of origin are used: to implement measures and instruments of commercial policy such as anti-dumping duties and safeguard measures; to determine whether imported products shall receive most-favoured-nation (MFN) treatment or preferential treatment; for the purpose of trade statistics; for the application of labeling and marking requirements; and for government procurement.