The Lauterpacht Centre for International Law (LCIL), University of Cambridge hosts a regular Friday lunchtime lecture series on key areas of International Law. Previous subjects have included UN peacekeeping operations, the advisory jurisdiction of the International Court of Justice, the crime of aggression, whaling, children and military tribunals, and theories and practices for proving individual criminal responsibility for genocide and crimes against humanity. This lecture, entitled 'What is an International Crime? And How This Question Matters Now for the Future of the ICC', was delivered at the Lauterpacht Centre on Friday 17th March 2017 by Nikolas Rajkovic, Professor and Chair of International Law at Tilburg University. For more information about the series, please see the LCIL website at http://www.lcil.cam.ac.uk