Southern Christian Leadership Conference (SCLC), civil-rights organization founded in 1957 by Martin Luther King, Jr., and headed by him until his assassination in 1968. Composed largely of African-American clergy from the South and an outgrowth of the Montgomery, Ala., bus boycott that King had led, it advocated nonviolent passive resistance as the means of securing equality for African Americans. It sponsored the massive march on Washington in 1963. Ralph Abernathy headed (1968-77) the SCLC after King's death, but it since has become less prominent. The SCLC continues to sponsor a number of programs, including voter registration and education and the Truth and Justice Campaign.