Gregory R. Erlandson is president of Our Sunday Visitor Publishing, which is based in Indiana and produced a number of Pope Benedict XVI’s works. Erlandson is co-author of the 2010 book Pope Benedict XVI and the Sexual Abuse Crisis: Working for Reform and Renewal. He also worked in Rome covering the Vatican for Catholic News Service.

Robert Mickens is editor-in-chief at Global Pulse, a Catholic magazine. He has been the Vatican correspondent for The Tablet, a Catholic weekly published in London. He is based in Rome.

Leo Ribuffo is a history professor at the Elliott School of International Affairs at George Washington University in Washington, D.C. He has written about the complex relationship between religion and American foreign policy.

Sandro Magister is a Vaticanologist and an Italian journalist whose website, Chiesa, has an English-language archive of Magister’s insider essays on the Vatican, including all the developments of Benedict’s papacy.

Chris Stewart is the California representative for Karate for Christ. He is based in Downey, Calif.

Matt Smith is pastor of Barabbas Road Church in La Jolla, Calif. He instituted a fitness ministry to attract new church members when other ministries failed.

Cissy Brady-Rogers is a marriage and family counselor in Arcadia, Calif., and was a contributor to The Religion of Thinness: Satisfying the Spiritual Hungers Behind Women’s Obsession With Food and Weight. She can discuss fitness, yoga, Christians practicing yoga, Christian-based weight loss, eating disorders, plastic surgery and sexuality. She can be contacted through her website.

The Christian Academy of Martial Arts is in Morgan Hill, Calif. It approaches martial arts with a Christian perspective.

Yahweh Yoga is a Christian-based yoga training academy that trains yoga teachers and offers Christ-oriented yoga classes. It is based in Chandler, Ariz.