In addition to global organizations, a lot of regional organizations have been formed across all continents. The initial form of integration was the establishment of a Free-trade zone, then a Customs Union, a Common Market, a Monetary Union, and finally the most complex form of organization an Economic Union. Today all countries in the world participate in some form of integration, and some even participate in multiple regional organizations. The integration process is not an easy and simple process, but a long and complex one. Some of the reasons why countries decide to participate in various regional economic organizations are the expansion of their markets, increase of competitiveness, better use of resources, more efficient production etc. The integration means that Member States have to conform to certain rules, and to connect in terms of development cooperation, in order to achieve the goal for which the organization was formed. An example of one the most successful regional economic organizations is certainly the European Union, which was formed back in 1951. It is still active today, increasing the number of its members and expanding its territory on the European continent.