Pierre d’Argent is special counsel at Foley Hoag and specializes in representing States before the International Court of Justice (ICJ) and other international courts and tribunals. He is first-class full-time professor (professeur ordinaire) at the University of Louvain in Belgium, where he holds the Public International Law Chair. Pierre also is guest professor at Leiden University in the Netherlands. He has published extensively in matters relating to international law and has lectured in many universities around the world, as well as at the UN Audiovisual Library of International Law. He has been director of studies and professor at The Hague Academy of International Law. In 2015, he was elected Associate Member of the Institute of International law.
Pierre has appeared before the ICJ as counsel and advocate to the DRC in the Arrest Warrant case (2001). He later served the ICJ as First Secretary (2009-2011).
Pierre has provided expert opinions to various law firms and government agencies. He notably acted as counsel to Belgium in the Ping An v. Belgium case under ICSID rules and in several cases before domestic courts.