The United Nations (UN) is an intergovernmental organization tasked with maintaining international peace and security, developing friendly relations among nations, achieving international co-operation, and being a centre for harmonizing the actions of nations. It was established after World War II, with the aim of preventing future wars, and succeeded the ineffective League of Nations. Its headquarters, which are subject to extraterritoriality, are in Manhattan, New York City, and it has other main offices in Geneva, Nairobi, Vienna and The Hague. The organization is financed by assessed and voluntary contributions from its member states. Its objectives include maintaining international peace and security, protecting human rights, delivering humanitarian aid, promoting sustainable development, and upholding international law. The UN is the largest, most familiar, most internationally represented and most powerful intergovernmental organization in the world. At its founding, the UN had 51 member states; there are now 193.