[3] Clark's books include God and the Brain, Strangers, Neighbors, Friends, Religion and the Sciences of Origins, Abraham’s Children, Return to Reason, The Story of Ethics, When Faith Is Not Enough, and 101 Key Philosophical Terms of Their Importance for Theology, many of which have been translated into multiple languages.
[5][6][7] Clark has lectured around the world and has served as director for international conferences on science and religion, interfaith cooperation, & Chinese philosophy.
He has worked extensively with the John Templeton Foundation, organizing many interfaith symposiums, notably “Liberty and Tolerance in an Age of Religious Conflict” at Georgetown University on the 10th anniversary of 9/11.
[8] That conference inspired a book of the same name in which fifteen influential practitioners of the Abrahamic religions argued for religious liberty and tolerance from their own faith traditions.
Contributors included former United States president Jimmy Carter, Indonesia's first democratically elected president Abhurrahman Wahid, Rabbis for Human Rights co founder, Rabbi Arik Asherman, Rana Husseini, Nurit Peled-Elhanan, the philosopher Nicholas Wolterstorff & theologian Miroslav Volf.