Roundtable on "Natural Law."  Acton Institute, Grand Rapids, Michigan, June, 2018.

James Wilson Institute.  Participant in the Wilson Institute’s biennial roundtables on natural law and jurisprudence, chaired by Hadley Arkes, 2011-2015

"Liberty in Walter Lippmann's The Public Philosophy."  Liberty Fund colloquium, Indianapolis, Indiana, 2009.

Author's roundtable on J. Budziszewski’s Evangelicals in the Public Square: Four Formative Voices, Christians in Political Science, meeting concurrently with the American Political Science Association, Chicago, Illinois, 2007.

"The Architecture of Christian Citizenship: Two Stories with Basement and Mezzanine."  Roundtable on "Social Issues and Civic Engagement" at the annual meeting of the Evangelical Philosophical Society, meeting concurrently with the Evangelical Theological Society, Washington, D.C., 2006.

Author's Roundtable on J. Budziszewski’s What We Can't Not Know: A Guide, Society of Catholic Social Scientists, meeting concurrently with the Annual Meeting of the American Political Science Association, Washington, D.C., 2005.

"Calvin on Liberty (Human and Divine) and Natural Law."  Liberty Fund colloquium, Miami Beach, Florida, 2002.

"A Public Conversation on Politics and Conscience."  Panel discussion with J. Budziszewski, Robert P. George, and John DiIulio, Center for Research on Religion in Urban Civil Society, University of Pennsylvania, Philadelphia, and Providence Forum, Philadelphia, 2002.

"After September 11: Biblical and Ethical Reflections on the Current Crisis."  Ethics and Public Policy Center, Washington, D.C., 2001.

"Biology, Morality, and Responsibility."  Liberty Fund colloquium, Tucson, Arizona, 2001.

"Law and Liberty in the Writings of John Locke."  Liberty Fund colloquium, Albuquerque, New Mexico, 2000.

"Liberty, Responsibility, and the Gulag."  Liberty Fund colloquium, South Woodstock, Vermont, 2000.

"Natural Law Theories of Ordered Liberty."  Liberty Fund colloquium, Charleston, South Carolina, 1999.

"Locke, Bayle, and Liberty of Conscience."  Liberty Fund colloquium, Albuquerque, New Mexico, 1999.

"Parental Rights in Education."  Liberty Fund colloquium, Milwaukee, Wisconsin, 1998.

"The Foundations of Law."  Center on the Foundations of Law at Deerfield, Illinois, 1997.

"Liberty, Democracy, and Technology in the Thought of George Grant and Yves R. Simon."  Liberty Fund colloquium, Savannah, Georgia,1997.

"Liberty and Social Contract in the Natural Law Tradition: From Pufendorf to Hume."  Liberty Fund colloquium, Dallas, Texas, 1993.

"Natural Law."  Conference, Department of Philosophy, University of Texas, Austin, Texas, 1993.

"Liberty and Natural Law in Thomas Aquinas."  Liberty Fund colloquium, Colorado Springs, Colorado, 1990.

"Are the Ancient and Modern Concepts of Liberty Compatible?"  Liberty Fund colloquium, Colorado Springs, Colorado, 1989.

"Toward A Normative Theory of Public Administration and the American States."  Center for Public Administration and Policy of Virginia Tech, Mountain Lake, Virginia, 1989.