“Creatively Collecting Data and Evidence,” in Peter Krause and Ora Szekely, eds. Stories from the Field: A Guide to Navigating Fieldwork in Political Science(New York, NY: Columbia University Press, 2020).
“Prison-Based Deradicalization” in Stian Lid and Stig Jarle Hansen, eds. Routledge Handbook of Deradicalisation and Disengagement (Abington, U.K: Routledge, 2020).
“ISIL and the Goal of Organizational Survival,” in Hilary Matfess and Michael Miklaucic, eds. Beyond Convergence: World Without Order (Washington DC: National Defense University Press, 2017.)
With Jonathan B. Wiener, “Terrorism and Weapons of Mass Destruction,” in Jonathan B. Wiener, Michael D. Rogers, James K. Hammitt, and Peter H. Sand, eds., The Reality of Precaution: Comparing Risk Regulation in the United States and Europe(Washington DC: Resources for the Future Press, 2011.)
With Dalia Mogahedand Tom Pyszczynski, “Religious Engagement and Violence,” in Chad Meistec, ed., The Oxford Handbook of Religious Diversity(London: Oxford University Press, 2010).
“Overview: Terrorism,” in Mark Green and Michele Jolin, eds., Change for America: A Progressive Blueprint for the 44thPresident(New York: Basic Books, 2009).
With Amit Modi, “Organizational Forms of Terrorism,” in Thomas Biersteker and Sue Eckert, eds.,Countering theFinancing of Terrorism, (New York: Routledge, 2008.)
“The Protean Enemy,” in Robert Art and Robert Jervis, eds., International Politics: Enduring Concepts and Contemporary Issues, 7thed. (Longman: 2005). Originally published in Foreign Affairs.
“Dreaded Risks and the Control of Biological Weapons,” in New Global Dangers, an International Security reader, MIT Press, July 2004. Originally published in International Security.
“Controlling Biological Weapons: A Risk-Tradeoff Analysis for a ‘Dreaded Risk’” in Janne Nolan The Transformation of Nonproliferation (The Century Foundation/Georgetown University, 2003).
“Terrorist Motivations and Unconventional Weapons,” in Peter Lavoy, Scott Sagan, and Jim Wirtz, ed., Planning the Unthinkable, (Ithaca: Cornell University Press, 2000).
“The Public Health Consequences of Terrorism” in C. Everett Koop, ed., Global Health in the 21stCentury(Jossey-Bass Publishers, 2000).
“The Covenant, the Sword, and the Arm of the Lord,” in Jonathan Tucker, ed., Toxic Terror(Cambridge: MIT Press, 2000).
“Larry Wayne Harris,” in Jonathan Tucker, ed., Toxic Terror, (Cambridge: MIT Press, 2000).
“Russia’s Crisis of Evolving Statehood: The Impact of the New Constitution and of the Parliamentary Elections,” in Stephen J. Blank, ed., Does Russian Democracy Have a Future?(Carlisle Barracks, Penn.: U.S. Army War College, 1994). Also published in Carol Timko, ed., Russia After the Elections (Berkeley: Berkeley-Stanford Program on Post Soviet Studies, 1994).
“Stalking Two Varieties of Poisonous Snakes: A Comparison of the Chemical and Nuclear Anti-Proliferation Regimes,” in J. B. Poole and R. Guthrie, eds., Verification Report 1994: Yearbook on Arms Control and Environmental Agreements(London: Pergamon Brassey, 1994).
“All’s Well That Ends Well: Verification and the CWC,” in J.B. Poole and R. Guthrie, eds., Verification Report 1993: Yearbook on Arms Control and Environmental Agreements(London: Pergamon Brassey, 1993.)
“Sanctions Against Violators of the CWC,” in Benoit Morel and Kyle Olson, eds., The Chemical Weapons Convention: The Shadow and the Substance (Boulder: Westview, 1993.)