The international legal order is in a process of transformation. But how transforms globalization the international legal order? This research programme provides a clearer framework to analyze this..

How do commissions of inquiry operating in conflict situations utilize international law, and how can inquiry findings be utilized by other bodies belonging to the international legal community?

The Frits Kalshoven International Humanitarian Law Competition, organised by the Netherlands Red Cross and Belgian Red Cross-Flanders, lets students explore the legal framework governing armed conflict. Eight teams from Belgium and the Netherlands competed in the 19th edition (23–27 February 2026) in…

How can international investment law and arbitration take account of the public interest in, and more broadly, the public dimension of, the relations between foreign investors and host States ?

For both Dutch and international students, a Humanities degree provides a strong foundation for a career that crosses borders.

At a time of urgent threats to both the planet and multilateralism, Brian McGarry (Assistant Professor of Public International Law at the Grotius Centre for International Legal Studies) has published a new volume on the past and future of international environmental law.

Are you thinking about studying International Relations? Learn more about the programme and watch the general introduction video.

International partnerships in which Leiden University participates.

The International Institute of Air and Space Law is one of the leading international academic research and teaching institutes in the world, specialising in legal and policy issues regarding aviation and space activities in the broadest sense of the word.

This PhD dissertation examines international responsibility for the crime of aggression from a public international law perspective. Under customary international law, as well as the amendments to the Rome Statute of the International Criminal Court adopted in the Review Conference in Kampala in 2010,…

Study information, Online Experience

This research cluster is a part of the Institute of Political Science’s research programme ‘Institutions, Decisions and Collective Behaviour’. Its members examine the sources, design, effects and contestation of norms, rules, institutionalised practices and formal organisations that operate across national…

The Team International Relations and European Studies addresses the interconnections and interdependence of contemporary global political, economic, security and culture from a multidisciplinary perspective rooted in the humanities. More specifically it is concerned with the study of international relations…

Almost a century passed since the much-celebrated judgement in the case concerning the Factory of Chorzów was delivered. This 1928 judgement of the Permanent Court of International Justice affirmed the essential principle of ‘reparation’ in international law, claiming that ‘restitution’ is the preferred…

By choosing Leiden University, you’ll be choosing to broaden your personal and academic horizons. You’ll be in excellent company too because you’ll be part of an inspiring community of students, lecturers and professors from all over the world. Founded in 1575, ours is the oldest university in the N…

In this chapter of the Elgar Encyclopedia of International Relations, Carraro explores how expertise is defined and contested in International Relations.

Using the League of Nations’ responses to early crises as an explorative historical case study, Political Scientist Gisela Hirschmann investigates how international organisations perceive and respond to existential threats.

The Private International Law Department provides academic education and performs research in the field of private international law.

How should the international community of states respond to genocide, war crimes and crimes against humanity? How can the perpetrators of international crimes be brought to justice? How can international crimes be prevented? How can the international community of states promote international consensus…

The Service Centre International Staff provides advice and different services to all international employees and guest researchers pursuing their academic careers in Leiden.

Understanding the complexities of world affairs requires an ability to think critically and to draw insights from a variety of perspectives, sources, and analytic frames. Leiden University’s Master of Arts in International Relations addresses these needs through distinctive humanities-based training…

This article offers an inaugural assessment of how silences implicate international law-making in cyberspace through descriptive and normative lenses.

In this article, the authors explore why there is substantial cross-national variation in the level of regulatory clarity surrounding cryptocurrencies

Study the MSc in Political Science: International Organisation at Leiden University in The Hague. Learn about international institutions, governance, and global policy.

If you are from abroad and you want to work at Leiden University, there is quite a lot to arrange.

This edited volume explores how artificial intelligence (AI) is transforming international conflict in cyberspace.

Ending the United Kingdom’s (UK) forty-seven year European Union (EU) membership has fundamentally transformed its relationship with the EU. After years of tumultuous negotiations, international law now once again governs the UK’s relationship with the EU. This has resulted in a sophisticated body of…

Four famous alumni introduced their favourite films at Leiden International Film Festival.