Uganda is a landlocked country located in Eastern Africa that borders the countries of Democratic Republic of the Congo, Kenya, Rwanda, South Sudan, and Tanzania. The terrain is mostly plateau with a rim of mountains and a southeastern shore of Lake Victoria. The government system is a republic. The chief of state and head of government is the President. Uganda has a mixed economic system in which there is a variety of private freedom, combined with centralized economic planning and government regulation. Uganda is a member of the African Union (AU), Africa Economic Community (AEC), and the Common Market for Eastern and Southern Africa (COMESA).