Repent America is a Philadelphia-based evangelistic organization that works against homosexuality, abortion and evolution.

David King is a senior lecturer in public policy at Harvard University in Cambridge, Mass.

Janet Porter is the president and founder of Faith2Action, a Christian advocacy group that works to influence politics and legislation. The group is based in Dania Beach, Fla.

J.J. Adler directed the 2007 documentary Unattached, about single Orthodox Jews in New York City. Watch the trailer.

Neil Clark Warren, a psychologist and former dean at Fuller Theological Seminary, co-founded and chairs the eHarmony online dating service. He has written several books about relationships, including Date … or Soul Mate?: How to Know if Someone Is Worth Pursuing in Two Dates or Less.

Christian Piatt is the co-author of MySpace to Sacred Space: God for a New Generation (2007) along with his wife Rev. Amy Piatt. He is an author, editor, speaker, musician and spoken word artist. He co-founded Milagro Christian Church in Pueblo, Colorado with his wife in 2004. Contact through the form on his website.

May Vanderbilt of San Francisco is a co-author of the Good Girl line of novels, including the 2007 title The Book of Jane, about single Christian women navigating modern life.

Trish Ryan, who lives outside Cambridge, Mass., wrote He Loves Me, He Loves Me Not: A Memoir of Finding Faith, Hope and Happily Ever After (2008).

Ethan Nichtern is the author of One City: A Declaration of Interdependence (2007), a Buddhist political treatise about, among other things, youth and political activism in a post 9-11 world. He is the founder of the Interdependence Project in New York City.