On 7 October 2026, the Advanced Master of Laws in International and European Law (IERE) marked the start of the new academic year with its traditional inaugural lecture. For this occasion, the programme welcomed Jean-Marie Henckaerts, Legal Adviser at the International Committee of the Red Cross (ICRC) and VUB alumnus, back to his alma mater.
In his lecture, entitled “Back to the Sources of International Law: Customary Law and Treaties in International Humanitarian Law”, Henckaerts explored the interplay between two fundamental sources of international law: customary international law and treaty law. Drawing on his extensive experience at the ICRC, he illustrated how both sources contribute to the protection of victims of armed conflict. Reflecting on his involvement in the ICRC study on customary international humanitarian law, Henckaerts explained how customary rules are identified through State practice and opinio juris. He highlighted their particular importance in non-international armed conflicts and in situations where treaty provisions do not apply or provide only limited protection. He also discussed the ongoing updating of the ICRC Commentaries on the Geneva Conventions, emphasising the importance of interpreting treaty provisions in light of evolving societal and technological developments. Contemporary challenges, including artificial intelligence and autonomous weapon systems, were also addressed.
A central message of the lecture was the enduring relevance of the fundamental principles and methods of international law. Henckaerts emphasised that a solid grounding in these foundations remains essential, regardless of the field of international law in which future legal professionals pursue their careers. He also shared personal reflections on his professional journey, encouraging students to gain international experience, develop their language skills and remain open to diverse career opportunities.
Following the lecture, the start of the 2026–2027 academic year was celebrated with a reception. Students, lecturers and other attendees had the opportunity to continue their discussions and mark the beginning of the new academic year together.
The IERE programme and the Department of Public Law sincerely thank Jean-Marie Henckaerts for his engaging and insightful lecture, as well as everyone who attended and contributed to this successful opening of the academic year. We wish all IERE students an enriching and successful academic year!
