This is the process of international integration operating between a limited number of countries, generally within the same continent. It is considered useful to distinguish regional integration from related concepts such as regionalism, regional cooperation, regional organization, regional movements, regional systems, or regional subsystems of a global system. The study of regional integration is concerned with explaining how and why states cease to be wholly sovereign, how and why they voluntarily mingle, merge, and mix with neighbours so as to lose the factual attributes of sovereignty while acquiring new techniques for resolving conflict between themselves. The other concepts may relate to stages on the way to regional integration, but they should not be confused with the resulting condition. (There is a difference of opinion as to whether the term refers solely to the terminal condition or also to the process by which it is achieved).
There has been a rapid extension and intensification of regional integration arrangements throughout all regions of the world, including the fast extension of groupings around major trading nations, the emergence of mixed arrangements between developing countries and their major trading partners, and a revival of integration among developing countries. These new developments are likely to exert a major impact on world trade and economic cooperation.