The National Association of Congregational Christian Churches (NACCC) is an association of about 400 churches providing fellowship for and services to churches from the Congregational tradition. The Association maintains its national office in Oak Creek, Wisconsin, a suburb of Milwaukee. The body was founded in 1955 by former clergy and laypeople of the Congregational Christian Churches in response to that denomination's pending merger with the Evangelical and Reformed Church to form the United Church of Christ in 1957.