The Association of Christian Churches of South Dakota officially began November 17, 1971, in Huron, South Dakota.

This historic meeting was the culmination of much planning and numerous meetings of the Executive Committee of the South Dakota Council of Churches and the Steering Committee of the soon-to-be organized Association of Christian Churches of South Dakota.  The Council had roots dating back to an early cooperative movement in Christian education through the Dakota Sunday School Association, founded in 1875 at Vermillion, Dakota Territory.  In 1943, the South Dakota Council of Christian Education and the Federated Council of Churches merged to become the South Dakota Council of Churches and Christian Education.  This convergence provided the medium through which fellowship and cooperation across denominational lines was possible and through which the ‘spirit of the ideal of unity’ was approachable.  Denominational leaders in South Dakota also were aware of the ecumenical dialogue that was created by Vatican II and Pope John XXIII.  Therefore, they chose to form a more inclusive organization within the state by replacing the South Dakota Council of Churches with the newly formed Association of Christian Churches of South Dakota.

One major hurdle of the Council of Christian Churches becoming the Association of Christian churches was in the transition itself.  The Council contained no American Lutheran or Catholic denominations.  These two denominations did not want any council or association speaking for them on issues.

This hurdle was crossed when the Association in its constitution mandated unanimity in all its programs and projects.

Ten judicatories representing nine denominations requested charter membership in the Association of Christian Churches.  They were: South Dakota District, American Lutheran Church; Christian Church – Disciples of Christ; Episcopal Diocese of South Dakota; Diocese of Rapid City – Roman Catholic Church; Red River Valley Synod, Lutheran Church in America; Reformed Church in America – Dakota Classis; Diocese of Sioux Falls – Roman Catholic Church; South Dakota Conference – United Church of Christ; South Dakota Annual Conference – United Methodist Church; and Presbytery of South Dakota, Synod of Lakes and Prairies, United Presbyterian Church.  Incorporation papers were filed with the state with all board members of the denominations included in the sighing of the papers.  Also included in the incorporation was the fact that the Association became the successor organization to the South Dakota Council of churches.

Membership rules of the Association were simple.  All Christian denominations, jurisdictions, churches, and units that accepted the Constitution and Bylaws of the Association and cooperated in some or all of its functions were eligible.  Dues which were used for the fixed costs of the Association, such as staff salaries, housing allowance, travel, approved programs, office expenses, etc., were to be shared by all member denominations or jurisdictions on a pro rata basis according to an equitable standard decided upon by the Executive Committee of the Association.