a legal designation for an area of land managed by a Native American tribe under the US Bureau of Indian Affairs, rather than the state governments of the United States in which they are physically located. There are 326 of these, each associated with a particular Nation. Not all of the country's 567 recognized tribes has one. Some tribes have more than one, some share, and others have none. Because tribes possess tribal sovereignty, even though it is limited, laws on tribal lands vary from the surrounding area.