The Leadership Conference on Civil Rights (LCCR) was founded in 1950 by three giants of the civil rights movement: A. Philip Randolph, founder of the Brotherhood of Sleeping Car Porters; Roy Wilkins, Executive Secretary of the NAACP; and Arnold Aronson, a leader of the National Jewish Community Relations Advisory Council. It is the nation's premier civil rights coalition, and has coordinated the national legislative campaign on behalf of every major civil rights law since 1957.

http://www.naacp.org/about/about_history.html

On February 12th the National Association for the Advancement of Colored People was founded by a multiracial group of activists, who answered "The Call." They initially called themselves the National Negro Committee. The mission of the National Association for the Advancement of Colored People is to ensure the political, educational, social and economic equality of rights of all persons and to eliminate racial hatred and racial discrimination.

The Southern Christian Leadership Conference (SCLC, first known as Southern Negro Leaders Conference on Transportation and Nonviolent Integration) is a civil rights organization founded in January 1957. Proposed by Bayard Rustin and later headed by Martin Luther King, Jr., the organization expressed these individuals' belief that a wider organization could be built upon the success of the Montgomery bus boycott, hence the original name. The organization focused on non-violent civil disobedience and believed that it could use that to gain the civil rights that African Americans lacked at the time. Other prominent members of the organization included Jesse Jackson, Ralph Abernathy, and Andrew Young. During the early 1960's, the group was considered more radical than the older NAACP and more conservative than the younger Student Nonviolent Coordinating Committee. SCLC had a mentoring relationship with SNCC in its earlier years, before SNCC abandoned its exclusive policy of nonviolence. (from www.en.wikipedia.org)

SCLC website
http://sclcnational.org/net/content/item.aspx?s=25461.0.12.2607
Link to the section explaining the early story of the organization

http://www.lib.usm.edu/~archives/m323.htm

Primary sources from the Ellin (Joseph and Nancy) Freedom Summer Collection. The bulk of this collection consists of materials that document the Civil Rights Movement and Freedom Summer in Hattiesburg, Mississippi.