Roger E. Olson (PhD, Rice University) is professor of theology at George W. Truett Theological Seminary of Baylor University in Waco, Texas. He is the author of The Story of Christian Theology: Twenty Centuries of Tradition & Reform, The Mosaic of Christian Belief: Twenty Centuries of Unity & Diversity, and The Westminster Handbook to Evangelical Theology. He is also coauthor of 20th-Century Theology: God & the World in a Transitional Age and Who Needs Theology? An Invitation to the Study of God (both with Stanley J. Grenz), and of The Trinity (with Christopher A. Hall).