Suzanne DiMaggio is a senior fellow at the Carnegie Endowment for International Peace, where she focuses on U.S. foreign policy toward Asia and the Middle East. She is one of the foremost experts and practitioners of diplomatic dialogues with countries that have limited or no official relations with the United States. For over two decades, she has led Track 1.5 and Track 2 conversations to help policymakers identify pathways for diplomatic progress on a range of issues, including regional security, nuclear nonproliferation, conflict prevention and resolution, crisis management, confidence building and negotiation, and bilateral relations. Her research and work draw on an approach to unofficial engagement she has been developing since the late 1990s, which began with a focus on U.S. relations with China, Russia, and Japan, and later expanded to Iran and the Middle East, Myanmar/Burma, and North Korea. 

She directs Carnegie’s U.S.-Iran Initiative, which is carried out through a combination of policy dialogue and scholarly research with the aim of exploring possible grounds for constructive diplomatic engagement and the development of mutually acceptable strategies for managing a range of contentious issues. The Initiative’s centerpiece is a long-running dialogue that she launched in 2002, which is often cited as a model for how to conduct informal diplomacy effectively and creatively. These efforts helped to establish a foundational basis for the secret talks between Iran and the Obama administration that led to the 2015 landmark comprehensive nuclear agreement. They also contributed to a de-escalation in tensions following the killing by the U.S. of Iranian General Qassem Soleimani and Iranian retaliatory strikes on Al Asad Airbase in Iraq in January 2020 and helped to avoid an escalatory spiral in the lead up to and during the April 2024 Israel-Iran confrontation.

Her work on North Korea included an unofficial Track 1.5 dialogue process that transitioned to the first official diplomatic discussions between the Trump administration and North Korean government in 2017. In 2011, she facilitated early talks that brought together senior officials from Myanmar and the U.S. to exchange views on the re-establishment of relations following the transition of Myanmar’s government. 

Before joining Carnegie, she was a senior fellow at New America (2014-2018), the vice president of global policy programs at the Asia Society (2007-2014), and the vice president of policy studies at the United Nations Association of the USA (1998-2007). She also was an adjunct professor at the School of Diplomacy & International Relations at Seton Hall University, where she taught undergraduate and graduate courses on the United Nations, multilateral diplomacy, and sustainable development.

DiMaggio is a board member of the Iran Project and the National Committee on North Korea and an advisory board member of Foreign Policy for America and the Vienna-based Open Nuclear Network. She also is an associate senior fellow at the Stockholm International Peace Research Institute (SIPRI) and a co-founder of the Quincy Institute for Responsible Statecraft, where she served as the inaugural board chair. She holds a BA from New York University and an MA from City College of New York (CUNY).