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10.16. Other customs and economic unions. There are many other regional agreements that aim at the promotion of economic integration and cooperation among its members, frequently with the goal of creating a common market.[11] However, a customs union, which is a critical step towards forming a common market, entails the harmonization of external tariffs and the removal of all tariffs on internal trade. Also, all non-tariff barriers to the free movement of goods would need to be gradually removed. Because of the need to give up parts of national sovereignty, i.e., on tariff matters, trade agreements and product safety, and because of the many consequences and the required work programme, the establishment of new full customs unions is expected to only progress but slowly. Even in cases where countries enter a customs union, it might be the case that customs controls would remain in place for security and other reasons. Given this situation, countries might seek other forms of economic integration such as regional trade agreements relying on customs controls for their enforcement.
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[1] For more information, please see Pascal Fontaine, Europe in 12 Lessons, October 2006, (Luxembourg, European Union, 2010), chap. 6, entitled “The Single Market”. Available from http://europa.eu/ abc/12lessons/index_en.htm.
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