This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Barna Group is an American market research firm founded by George and Nancy Barna in 1984 as the Barna Research Group, specializing in survey research on the religious beliefs, practices and generational trends of Americans, particularly evangelical Christians. The firm conducts its research primarily through telephone and online panel surveys, a methodology it has maintained across four decades of continuous operation, publishing its findings as standalone research reports, books and articles rather than through a single flagship periodical the way some rival research bodies do.
In 2004 the firm restructured from Barna Research Group into its present name, Barna Group, a change of corporate form rather than of mission, and it remains headquartered in Ventura, California, as a private research and polling firm rather than a nonprofit or an arm of any single denomination. Its ongoing State of the Church research series, published annually, has become one of the standard reference points American religious institutions cite when tracking their own membership and belief trends over time.