Laws, institutions, or practices which make trade between countries more difficult or expensive than trade within countries. Some are deliberately designed to discourage trade: tariff, that is special taxes on imports, come under this heading. In many countries tariffs have been greatly reduced under the General Agreement on Tariffs and Trade (GATT), and various groups of countries including the European Union (EU) and the North American Free Trade Agreement (NAFTA) between Canada, Mexico, and the United States have reduced or removed tariffs on trade between member countries. Other, non-tariff barriers, such as quota restrictions and voluntary export restraint (VERs), however, have become increasingly common in recent years. Barriers to trade are also imposed by national differences in matters such as health and safety standards, labelling requirements, and weights and measures regulations. While these are not necessarily intended to act as barriers to trade, the need to modify products to conform to local requirements, and the documentation required to certify that this has been done, tend to impose costs and delays on international trade in excess of those experienced in domestic trade. Effective trade barriers are also imposed by public procurement, which often give preferential treatment to domestic over foreign suppliers, as the result of legal requirements, through acts of policy, or simply through better information about domestic sources. The EU attempts to prevent this domestic bias in public procurement, so far as member countries are concerned, but with limited success.

• convergent series
• convertibility
• convertible currency
• convertible debenture
• convexity
• co-operation
• co-operative society
• coordinates
• co-ordination failure
• co-ordination, policy
• copyright
• core
• core inflation
• corner
• corner a market
• corner solution
• corporate equity
• corporate income tax
• corporate sector
• corporation
• Corporation Tax
• corporatism
• correlation
• correlation of returns
• corruption