Mercosur is an example of an international common market.
A common market is a type of trading block that is made up of a combination of customs union and free trade zone. Countries act as a bloc, defining the same tariffs when trading out so as not to avoid internal competition, eliminating border tariffs among them and allowing the free transit of people, as well as capital and services; freedom to provide services and freedom of establishment. It can also be called a single market. It is established in the middle of treaties between the countries which are associated with the ultimate purpose of eliminating existing customs barriers in foreign trade by establishing common customs duties for originating products in any other country outside the group as well as another series of uniform economic policies for the benefit of the countries of the community.
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