Scott D. Sagan is Co-Director and Senior Fellow at the Center for International Security and Cooperation, the Caroline S.G. Munro Professor of Political Science, and the Bass University Fellow in Undergraduate Education at Stanford University. He also serves as Co-Chair of the American Academy of Arts and Sciences’ Committee on International Security Studies. Before joining the Stanford faculty, Sagan was a lecturer in the Department of Government at Harvard University and served as special assistant to the director of the Organization of the Joint Chiefs of Staff in the Pentagon.

Sagan is the author of Moving Targets: Nuclear Strategy and National Security (Princeton University Press, 1989); The Limits of Safety: Organizations, Accidents, and Nuclear Weapons (Princeton University Press, 1993); and, with co-author Kenneth N. Waltz, The Spread of Nuclear Weapons: An Enduring Debate (W.W. Norton, 2012). He is the co-editor of Insider Threats (Cornell University Press, 2017) with Matthew Bunn; and co-editor of The Fragile Balance of Terror (Cornell University Press, 2022) with Vipin Narang. Sagan was also the guest editor of a two-volume special issue of Daedalus: Ethics, Technology, and War (Fall 2016) and The Changing Rules of War (Winter 2017).

Recent publications include “Creeds and Contestation: How US Nuclear and Legal Doctrine Influence Each Other,” with Janina Dill, in a special issue of Security Studies (December 2025); “Kettles of Hawks: Public Opinion on the Nuclear Taboo and Noncombatant Immunity in the United States, United Kingdom, France, and Israel”, with Janina Dill and Benjamin A. Valentino in Security Studies (February 2022); “The Rule of Law and the Role of Strategy in U.S. Nuclear Doctrine” with Allen S. Weiner in International Security (Spring 2021); “Does the Noncombatant Immunity Norm Have Stopping Power?” with Benjamin A. Valentino in International Security (Fall 2020); and “Just War and Unjust Soldiers: American Public Opinion on the Moral Equality of Combatants” and “On Reciprocity, Revenge, and Replication: A Rejoinder to Walzer, McMahan, and Keohane” with Benjamin A. Valentino in Ethics & International Affairs (Winter 2019).

In 2022, Sagan was awarded Thérèse Delpech Memorial Award from the Carnegie Endowment for International Peace at their International Nuclear Policy Conference. In 2017, he received the International Studies Association’s Susan Strange Award which recognizes the scholar whose “singular intellect, assertiveness, and insight most challenge conventional wisdom and intellectual and organizational complacency" in the international studies community. Sagan was also the recipient of the National Academy of Sciences William and Katherine Estes Award in 2015, for his work addressing the risks of nuclear weapons and the causes of nuclear proliferation. The award, which is granted triennially, recognizes “research in any field of cognitive or behavioral science that advances understanding of issues relating to the risk of nuclear war.” In 2013, Sagan received the International Studies Association's International Security Studies Section Distinguished Scholar Award. He has also won four teaching awards: Stanford’s 1998-99 Dean’s Award for Distinguished Teaching; Stanford's 1996 Hoagland Prize for Undergraduate Teaching; the International Studies Association’s 2008 Innovative Teaching Award; and the Monterey Institute for International Studies’ Nonproliferation Education Award in 2009.     

Siegfried S. Hecker is a professor emeritus (research) in the Department of Management Science and Engineering and a senior fellow emeritus at the Freeman Spogli Institute for International Studies (FSI). He was co-director of CISAC from 2007-2012. From 1986 to 1997, Dr. Hecker served as the fifth Director of the Los Alamos National Laboratory. Dr. Hecker is an internationally recognized expert in plutonium science, global threat reduction, and nuclear security.

Dr. Hecker’s current research interests include nuclear nonproliferation and arms control, nuclear weapons policy, nuclear security, the safe and secure expansion of nuclear energy, and plutonium science. At the end of the Cold War, he has fostered cooperation with the Russian nuclear laboratories to secure and safeguard the vast stockpile of ex-Soviet fissile materials. In June 2016, the Los Alamos Historical Society published two volumes edited by Dr. Hecker. The works, titled Doomed to Cooperate, document the history of Russian-U.S. laboratory-to-laboratory cooperation since 1992.

Dr. Hecker’s research projects at CISAC focus on cooperation with young and senior nuclear professionals in Russia and China to reduce the risks of nuclear proliferation and nuclear terrorism worldwide, to avoid a return to a nuclear arms race, and to promote the safe and secure global expansion of nuclear power. He also continues to assess the technical and political challenges of nuclear North Korea and the nuclear aspirations of Iran.

Dr. Hecker joined Los Alamos National Laboratory as graduate research assistant and postdoctoral fellow before returning as technical staff member following a tenure at General Motors Research. He led the laboratory's Materials Science and Technology Division and Center for Materials Science before serving as laboratory director from 1986 through 1997, and senior fellow until July 2005.

Among his professional distinctions, Dr. Hecker is a member of the National Academy of Engineering; foreign member of the Russian Academy of Sciences; fellow of the TMS, or Minerals, Metallurgy and Materials Society; fellow of the American Society for Metals; fellow of the American Physical Society, honorary member of the American Ceramics Society; and fellow of the American Academy of Arts and Sciences.

His achievements have been recognized with the Presidential Enrico Fermi Award, the 2020 Building Bridges Award from the Pacific Century Institute, the 2018 National Engineering Award from the American Association of Engineering Societies, the 2017 American Nuclear Society Eisenhower Medal, the American Physical Society’s Leo Szilard Prize, the American Nuclear Society's Seaborg Medal, the Department of Energy's E.O. Lawrence Award, the Los Alamos National Laboratory Medal, among other awards including the Alumni Association Gold Medal and the Undergraduate Distinguished Alumni Award from Case Western Reserve University, where he earned his bachelor's, master's, and doctoral degrees in metallurgy.

Scott D. Sagan is Co-Director and Senior Fellow at the Center for International Security and Cooperation, the Caroline S.G. Munro Professor of Political Science, and the Bass University Fellow in Undergraduate Education at Stanford University. He also serves as Co-Chair of the American Academy of Arts and Sciences’ Committee on International Security Studies. Before joining the Stanford faculty, Sagan was a lecturer in the Department of Government at Harvard University and served as special assistant to the director of the Organization of the Joint Chiefs of Staff in the Pentagon.

Sagan is the author of Moving Targets: Nuclear Strategy and National Security (Princeton University Press, 1989); The Limits of Safety: Organizations, Accidents, and Nuclear Weapons (Princeton University Press, 1993); and, with co-author Kenneth N. Waltz, The Spread of Nuclear Weapons: An Enduring Debate (W.W. Norton, 2012). He is the co-editor of Insider Threats (Cornell University Press, 2017) with Matthew Bunn; and co-editor of The Fragile Balance of Terror (Cornell University Press, 2022) with Vipin Narang. Sagan was also the guest editor of a two-volume special issue of Daedalus: Ethics, Technology, and War (Fall 2016) and The Changing Rules of War (Winter 2017).

Recent publications include “Creeds and Contestation: How US Nuclear and Legal Doctrine Influence Each Other,” with Janina Dill, in a special issue of Security Studies (December 2025); “Kettles of Hawks: Public Opinion on the Nuclear Taboo and Noncombatant Immunity in the United States, United Kingdom, France, and Israel”, with Janina Dill and Benjamin A. Valentino in Security Studies (February 2022); “The Rule of Law and the Role of Strategy in U.S. Nuclear Doctrine” with Allen S. Weiner in International Security (Spring 2021); “Does the Noncombatant Immunity Norm Have Stopping Power?” with Benjamin A. Valentino in International Security (Fall 2020); and “Just War and Unjust Soldiers: American Public Opinion on the Moral Equality of Combatants” and “On Reciprocity, Revenge, and Replication: A Rejoinder to Walzer, McMahan, and Keohane” with Benjamin A. Valentino in Ethics & International Affairs (Winter 2019).

In 2022, Sagan was awarded Thérèse Delpech Memorial Award from the Carnegie Endowment for International Peace at their International Nuclear Policy Conference. In 2017, he received the International Studies Association’s Susan Strange Award which recognizes the scholar whose “singular intellect, assertiveness, and insight most challenge conventional wisdom and intellectual and organizational complacency" in the international studies community. Sagan was also the recipient of the National Academy of Sciences William and Katherine Estes Award in 2015, for his work addressing the risks of nuclear weapons and the causes of nuclear proliferation. The award, which is granted triennially, recognizes “research in any field of cognitive or behavioral science that advances understanding of issues relating to the risk of nuclear war.” In 2013, Sagan received the International Studies Association's International Security Studies Section Distinguished Scholar Award. He has also won four teaching awards: Stanford’s 1998-99 Dean’s Award for Distinguished Teaching; Stanford's 1996 Hoagland Prize for Undergraduate Teaching; the International Studies Association’s 2008 Innovative Teaching Award; and the Monterey Institute for International Studies’ Nonproliferation Education Award in 2009.     

Michael Tomz is the William Bennett Munro Professor in Political Science and Chair of the Department of Political Science at Stanford University. He is also a Senior Fellow at the Stanford Institute for Economic Policy Research, a Senior Fellow at the Stanford King Center on Global Development, and the Landreth Family University Fellow in Undergraduate Education.

Tomz has published in the fields of international relations, American politics, comparative politics, and statistical methods. He is the author of Reputation and International Cooperation: Sovereign Debt across Three Centuries and numerous articles in political science and economics journals.

Tomz received the International Studies Association’s Karl Deutsch Award, given to a scholar who, within 10 years of earning a Ph.D., has made the most significant contribution to the study of international relations. He has also won the Giovanni Sartori Award for the best book developing or applying qualitative methods; the Jack L. Walker Award for the best article on Political Organizations and Parties; the best paper award from the APSA section on Elections, Public Opinion and Voting Behavior; the best paper award from the APSA section on Experimental Research; and the Okidata Best Research Software Award. His research has been supported by the National Science Foundation.

Tomz has received numerous teaching awards, including the Dean’s Award for Distinguished Teaching and the Cox Medal for Excellence in Fostering Undergraduate Research. In 2017 he received Stanford’s highest teaching honor, the Walter J. Gores Award for Excellence in Teaching.

Tomz holds a Ph.D. from Harvard University; a master’s degree from the University of Oxford, where he was a Marshall Scholar; and an undergraduate degree from Georgetown University. He has been a visiting scholar at the Center for Advanced Study in the Behavioral Sciences, the Federal Reserve Bank of Minneapolis, the Hoover Institution, the Institute for Research in the Social Sciences, and the International Monetary Fund.