Written by Kerry Walters. Walters gives an overview of the history and philosophy of Atheism.

Howard Hendricks is chairman of the Center for Christian Leadership at Dallas Theological Seminary in Texas.

Written by Robin Le Poidevin. Le Poidevin explains agnosticism as an ideology and writes about its history and development.

The Rev. Frederick W. Schmidt is director of spiritual formation and Anglican studies and an associate professor of Christian spirituality at Southern Methodist University, Dallas. He is the author of A Still Small Voice: Women, Ordination and the Church (Syracuse University Press, 1996).

Written by S.T. Joshi. Joshi writes about the history and development of modern Atheism.

William C. Placher is a professor of philosophy and religion and LaFollette Distinguished Professor in the Humanities at Wabash College in Crawfordsville, Ind. His books include, as editor, Callings: Twenty Centuries of Christian Wisdom on Vocation (Eerdmans Publishing, 2005).

James R. Wood is a professor emeritus of sociology at Indiana University, Bloomington, and was part of a team of scholars working on a project called “Organizing Religious Work for the 21st Century.”

The Rev. Ken Davis is director of the Program for Formation of Hispanic Ministry at St. Meinrad School of Theology in Indiana and co-author of Emerging Voices, Urgent Choices: Essays on Latino/a Religious Leadership (Brill Academic Press, 2006).

Paula Nesbitt is a visiting associate professor of sociology at the University of California, Berkeley. She is the author of Feminization of the Clergy in America: Occupational and Organizational Perspectives (Oxford University Press, 1997).