The Under Secretary for Political Affairs, Thomas A. Shannon, Jr., is the Department's fourth-ranking official. The Under Secretary serves as the day-to-day manager of overall regional and bilateral policy issues, and oversees the bureaus for Africa, East Asia and the Pacific, Europe and Eurasia, the Near East, South and Central Asia, the Western Hemisphere, and International Organizations.
The Assistant Secretaries of the geographic bureaus and offices advise the Under Secretary and guide the operation of the U.S. diplomatic missions within their regional jurisdiction. They are assisted by Deputy Assistant Secretaries, office directors, post management officers, and country desk officers. These officials work closely with U.S. embassies and consulates overseas and with foreign embassies in Washington, DC.
The Bureau of International Organization Affairs (IO) develops and implements the policies of the U.S. Government within the United Nations and its affiliated agencies, as well as within certain other international organizations. The IO Bureau engages in what is known as multilateral diplomacy to promote and defend the many overlapping interests of the American people. The IO Bureau also promotes effective and efficient management within international organizations.