Walter Ralston Martin, American minister and author, founded the Christian Research Institute (died 1989)

Walter Ralston Martin was an American Baptist Christian minister and author who founded the Christian Research Institute in 1960 as a parachurch ministry specializing as a clearing-house of information in both general Christian apologetics and in countercult apologetics. As the author of the influential The Kingdom of the Cults (1965), he has been dubbed by the conservative Christian columnist Michael J. McManus, the "godfather of the anti-cult movement".

The Christian Research Institute (CRI) is an evangelical Christian apologetics ministry. It was established in October 1960 in the state of New Jersey by Walter Martin (1928–1989). In 1974, Martin relocated the ministry to San Juan Capistrano, California. The ministry's office was relocated in the 1990s near Rancho Santa Margarita. In 2005, the organization moved to its present location in Charlotte, North Carolina.