U.S.–South Korea Status of Forces Agreement (Hangul:; Hanja:, SOFA); Official name: Agreement under Article 4 of the Mutual Defence Treaty between the Republic of Korea and the United States, Regarding Facilities and Areas and the Status of United States Armed Forces in the Republic of Korea) is an agreement between South Korea and the U.S. approved and enacted in 1967 and revised in 1991 and 2001. It is a status of forces agreement that concerns the treatment of United States Forces in South Korea.