A Native American government consisting of a Judicial, Legislative, and Executive Branches located in Sells, Arizona. The reservation covers 2.8 million acres bordering Tucson, Arizona on the East and Mexico on the South. There are about 30,000 enrolled members, half of whom live on the reservation in eleven districts. The Executive Branch has an elected chairman that serves a four-year term. The Legislative Council is comprised of two elected representatives from each district.