Abstract
This article seeks to identify the factors that influence the success of negotiations on the origin of regional regimes. To this end, it deals with two cases, namely with the establishing of the single market of the European Economic Community and with the establishing of the Common Market of the South (Mercado Común del Sur, Mercosur).
Both case studies clearly confirm the impact of state interests and the related activity of the most interested states on the success of negotiations. In addition, the article also shows that the success of negotiations can also be determined in some cases by the existence and activity of a hegemon and institutional agents.
The key strategy used in attempts to initiate or reinforce regional cooperation in various parts of the world should therefore include an effort to engage a hegemon (if it exists) and establish institutional agents directed at providing the necessary expertise and independent mediation.