Regional organizations have started to have a considerable impact on global politics since the end of the Second World War.

There are two waves of regionalism. The first wave started after the Second World War. The second wave started after the end of the bipolar system.

“Political will to create a formal arrangement among states on a geographically restricted basis. Since its main participants are governments, it can be expressed as an artificial, top-down process.” (Hoshiro, Regionalization and Regionalism in East Asia, p. 2)

Political organizations seek to cooperate in political and foreign policy issues.

They are established by the nation states with the aim of cooperation in economic issues.

Security organizations aim to protect member states from common risks and threats. Risks and threats can stem from inside or outside the region.

"Old regionalism" is a type of regionalism in which states play the most important role. According to this approach, regions are considered to be fixed structures.

According to this approach, Multiple actors, like states, business communities and NGO’s play the fundamental role in the establishment of regions. Regions are considered as not fixed, but constructed entities.

Shallow regionalism represents a kind of regionalism that is based on cooperation among states.

Institutional regionalism defines deepening of the cooperation among states.

In the closed regionalism, regional organizations try to protect themselves from the competition stemming from outside.

In the open regionalism, organizations are open to global competition.

Ernst Haas defines integration as follows:
• “the process whereby political actors in several distinct national settings are persuaded
• to shift their loyalties, expectations and political activities toward a new and larger
• center, whose institutions possess or demand jurisdiction over the preexisting national states.” (Haas, “International Integration”, 1963, p. 7)

Regional organizations can be classified into two groups according to their organizational structures. Some of them just focus on cooperation in certain issue areas, however, the second group of them integrate their policies by moving beyond the Westphalian understanding of sovereignty.

Integration might involve two characteristics: pooling and delegation.

The concept of pooling is related to the decision-making mechanism within the organization.

In the case of pooling, member states decide by qualified majority voting.

In the case of delegation, the decision making authority is transferred to regional organization.

Spillover is spread of the area of cooperation or integration from one field to another. It is argued by functionalists and neofunctionalists that the direction of spillover is from technical fields to political issues.

Diffusion is the affect of an organization on institutional structure or decision making mechanism of another organization.