In the two years since Russia’s full-scale invasion of Ukraine began, the fighting has caused widespread horror and devastation. Over 10,000 civilians have been killed and more than half a million people injured. Still millions of others are internally displaced, seeking refuge abroad, or are in dire need of humanitarian assistance. The idea of war – and how to prevent it – was a central concern when 51 nations came together to form the United Nations over seven decades ago. Russia’s invasion of Ukraine poses deep challenges to the international rules-based order and raises complex questions of international law, not only for Ukraine, but for nations around the world.In partnership with the Ukrainian Association of International Law, which worked with other stakeholders such as the Ukrainian Bar Association, the American Society of International Law helped to convene a gathering of international lawyers in Lviv, Ukraine in December 2023. Lviv was home to three giants in the field of international law: Hersch Lauterpacht, Rafael Lemkin, and Louis Sohn. Lauterpacht developed the concept of crimes against humanity, Lemkin pioneered the term “genocide,” and pushed for the adoption of the U.N. Genocide Convention, and Sohn played a pivotal role in helping to conceptualize article 51 of the U.N. Charter on the right of self-defense. Many of those who gathered in Lviv are now sharing their reflections on the meeting in a Just Security symposium. Joining the show to discuss the symposium are four of its editors, Kateryna Busol, Olga Butkevych, Rebecca Hamilton, and Gregory Shaffer.  Kateryna is a Ukrainian lawyer and an Associate Professor at the National University of Kyiv-Mohyla Academy. Olga is President of the Ukrainian Association of International Law and Chaired Professor of Law at Kyiv’s National University of Taras Shevchenko. Rebecca is an Executive Editor at Just Security and a Professor of Law at American University, Washington College of Law. Greg is the Scott K Ginsburg Professor of International Law at Georgetown University Law Center and the President of the American Society of International Law. Show Notes:  Kateryna Busol (@KaterynaBusol)Olga ButkevychRebecca Hamilton (@bechamilton)Gregory Shaffer (@gregorycshaffer) Paras Shah (@pshah518) Just Security’s symposium “International Law in the Face of Russia’s Aggression in Ukraine: The View from Lviv” Patryk I. Labuda’s (@PILabuda) Just Security article “Accountability for Russian Imperialism in the ‘Global East’”Just Security’s International Law coverageJust Security’s Russia-Ukraine War coverageMusic: “Broken” by David Bullard from Uppbeat: https://uppbe