Géraldine Mattioli-Zeltner is the advocacy director of the International Justice Program, and is responsible for conducting advocacy on the International Criminal Court (ICC) and other issues related to accountability for grave international crimes. She focuses on justice issues in the Democratic Republic of Congo, universal jurisdiction, and advocacy on international justice matters with the European Union institutions and member states. Before joining Human Rights Watch, she worked in London with the International Justice Project of Amnesty International and with Field Diplomacy Initiative, a Belgian non-governmental organization, on the issue of justice for past serious human rights violations in Rwanda. Mattioli-Zeltner first joined Human Rights Watch in October 2002 to work on protecting the Belgian universal jurisdiction law, which had come under attack at the time. As the first judges and prosecutor of the ICC were elected and arrived in The Hague, she expanded her work to monitoring the institution and helped conduct Human Rights Watch’s advocacy towards the court. Mattioli-Zeltner studied international relations and international law at the French University of Aix-en-Provence and she received a master’s degree from the European Inter-University Centre for Human Rights and Democratisation.