International migration is one of these global challenges which require certain response from the governments but also demand a close cooperation among the national states. One of the most important form of states' collaboration to face the effects of massive migration processes takes place through international organizations. The main aim of the text is to present the origin, background and evolution of the activities of international organizations related to migration and addressed directly and indirectly to migrants. Among numerous cases, two are examined in details: the United Nations as the foremost forum to deal with migration issue at the global level, and the EU as the fully developed regional system of migration management based on common law, institutions and funds. Through last decades the universal system of the labour migrants rights protection has been also formed, its main institutions and legal fundaments are also presented here.