Tariff
In contrast, in economic theory tariffs are viewed as a primary element in international trade with the function of the tariff being to influence the flow of trade by lowering or raising the price of targeted goods to create what amounts to an artificial competitive advantage. When tariffs are viewed and used in this fashion, they are addressing the country's and the competitors' respective economic healths in terms of maximizing or minimizing revenue flow rather than in terms of the ability to generate and maintain a competitive advantage which is the source of the revenue. As a result, the impact of the tariffs on the economic health of the country are at best minimal but often are counter-productive.
Non-tariff barriers to trade
Non-tariff barriers to trade (NTBs) or sometimes called "Non-Tariff Measures (NTMs)" are trade barriers that restrict imports or exports of goods or services through mechanisms other than the simple imposition of tariffs. The Southern African Development Community (SADC) defines a non-tariff barrier as ""any obstacle to international trade that is not an import or export duty. They may take the form of import quotas, subsidies, customs delays, technical barriers, or other systems preventing or impeding trade."" According to the World Trade Organization, non-tariff barriers to trade include import licensing, rules for valuation of goods at customs, pre-shipment inspections, rules of origin ('made in'), and trade prepared investment measures.