Mustard Seed Associates in Seattle is a network for Christians interested in cultural innovation. It is a resource for information about cohousing.

The Robert Green Ingersoll Birthplace Museum in Dresden, N.Y., is described as America’s only freethought museum. It tells the story of the noted 19th-century agnostic orator, including his most famous speech, “Ghosts.”

Project Reason is a nonprofit foundation dedicated to promoting secular values and scientific knowledge. Sam Harris is co-founder and chairman. Contact through the website.

The Institute for the Study of Secularism in Society and Culture strives to foster understanding of the role of secular values and the process of secularization in today’s society. The nonpartisan, multidisciplinary institute is based at Trinity College in Hartford, Conn., and is part of the college’s Program on Public Values. Barry Kosmin is director.

The Humanist Society certifies humanist celebrants. It’s based in Washington, D.C. Sarah Ameigh is communications and policy assistant.

The Humanist Institute explores humanist values and trains future leaders. Its seminars are held primarily in New York City and Washington, D.C. Kendyl R. Gibbons and Carol Wintermute are co-deans of the institute. Contact through the website.

FreeThoughtAction aims to spread the message of rational thought through billboards and other means and thereby grow the ranks of the freethought community.

Camp Quest was established in 1996 as the first residential summer camp in the U.S. aimed at children from freethinking families. Amanda Metskas is executive director.

The American Ethical Union espouses “deed before creed.” It neither affirms nor denies a belief in God and has no set theology or doctrines about life’s mysteries. Bart Worden is executive director.