Members of the organization are from various movements, such as evangelicalism, and represent several Christian traditions including the Lutherans, Catholics, Methodists, Presbyterians, Baptists, Anabaptists, and the Orthodox.

Moon originated the idea of a group; he talked Moody Bible Institute president William H. Houghton into inviting a number of scientists with similar Christian views to Chicago to discuss its formation.

F. Alton Everest, Peter W. Stoner, Russell D. Sturgis, John P. VanHaitsma, and Irving A. Cowperthwaite attended, and the ASA formed from this meeting.

Everest, a conservative Baptist electrical engineer at Oregon State College in Corvallis, served as president of the Affiliation for its first decade.

[2] During the 1940s and 1950s the group provided an evangelical forum for discussing the alleged merits and drawbacks of the theory of evolution, and for evaluating the works of prominent creationists such as George McCready Price (1870–1963) and Harry Rimmer (1890–1952).