ABSTRACT
The history of international organizations dates back hundreds of years, with a major growth in their number, size and mandate since 1945. While there were merely 37 international organizations in 1909, today more than 250 major agencies are in place, along with hundreds of smaller bureaucracies such as treaty secretariats or United Nations programmes. International organizations, like most other actors in world politics, have been challenged in the last decades through major transformations in the international system, ranging from economic globalization to the end of the bipolar order, global environmental degradation, the information revolution, or the rise of transnational terrorism.
