Zambia joined the UN on 1 December 1964 and participates in ECA and all the non-regional specialized agencies except IMO. It belongs to the African Development Bank, Commonwealth of Nations, G-77, and AU, and is a signatory of the Law of the Sea and a member of the WTO. Located in Zambia are the headquarters of the International Red Locust Control Organization for Central and Southern Africa, as well as an office of the UN High Commissioner of Refugees and a regional office of the UN Institute for Namibia, established to provide training for future administrators of an independent Namibian state. Zambia belongs to the Southern African Development Community (SADC) and the Preferential Trade Area for Eastern and Southern Africa. While supporting liberation movements, Zambia has played a pivotal role in the search for détente in southern Africa.