The article examines the different approaches in the international law to the definition of integration, its causes and motives. Integration is seen by the authors in two aspects, namely, as a process and as a result. In this regard, integration results in creating a certain space, a territory in which the integration processes occurred, and simultaneously in establishing the institutional framework to manage the integration process. The authors argue that noticeable reduction in a number of currencies in the world signals the objective character of policy trends towards monetary integration. The conclusions are based on the analysis of monetary integration in Latin America.