Combining insights from regulation theory, law and computer science, this book explores policy and digital enforcement solutions that could strengthen EU consumer protection against dark patterns – a policy priority in recent years and the near future. The book illustrates why more technology-specific…

In theory, states can gain security by acquiring internal arms or external allies. Yet the empirical literature offers mixed findings: some studies find arms and allies to be substitutes, while others find them to be complements. Political scientists Matthew Digiuseppe (Leiden University) and Paul Poast…

William Lippert investigates the effect of delegation to an agreement executor on success of conventional arms control agreements in Europe.

This open access volume surveys the state of the field to examine whether a fifth wave of deterrence theory is emerging. Bringing together insights from world-leading experts from three continents, the volume identifies the most pressing strategic challenges, frames theoretical concepts, and describes…

Van Vark defended her dissertation 'Separation and immersion: the changing role of the armed forces in Northwestern liberal democracies’ on 17 October 2025. The doctoral research was supervised by Maartje van der Woude and Erwin Muller.

Political scientist Corinna Jentzsch (Leiden University) about the organisation of rebel and government auxiliaries in the civil war in Mozambique (1976–1992).

The world is full of wars, and no war is without its dead. What happens to the bodies of fatal casualties of armed conflict? The winner of the faculty Jongbloed Thesis Prize 2015 is Welmoet Wels (Public International Law). Her thesis Dead body management in armed conflict: paradoxes in trying to do…

A story of Two Mosuls, The Resurrection of the Iraqi Armed Forces and the military defeat of ISIS. In this article, published in the Journal of Strategic Studies, the authors Maarten Broekhof, Martijn Kitzen and Frans Osinga discuss the military adaptation by the Iraqi armed forces and their role in…

On 21 March 2019, James Welch defended his thesis 'The Grotius Sanction: Deus Ex Machina. The legal, ethical, and strategic use of drones in transnational armed conflict and counterterrorism'. The doctoral research was supervised by Prof. dr. P.B Cliteur.

How have the armed forces of the United Kingdom, the Netherlands and Belgium adapted to the OMLT task in Afghanistan, and what institutional changes have materialised as a consequence of this adaptation?

On 28 January 2015, Prof. Ton Liefaard participated in a panel discussion on

On 24 November 2016, Dr Giulia Pinzauti, Assistant Professor of Public International Law at the Grotius Centre for International Legal Studies, spoke on “The protective reach of the law of armed conflict” at the PIL Lunchtime Discussion Group at All Souls College in Oxford.

This new Casebook features the work of an international, interdisciplinary research group entitled ‘The Joust as Performance: Pas d’armes and Late Medieval Chivalry’.

The Geneva Conventions and customary international humanitarian law clearly prohibit any attacks on medical units and establishments during armed conflicts. Unfortunately, despite this clear prohibition, medical personnel and medical facilities continue to be the subject of attacks. Doctors now risk…

Francesca Albanese, UN Special Rapporteur for human rights in the occupied Palestinian territories, visited Leiden Law School on 8 December within the scope of International Human Rights Day.

Climate change is one of the largest challenges faced by humanity. To combat this research into alternatives to fossil fuels is ongoing. Dihydrogen is considered a good alternative fuel, since its burning only forms water.

Why do some civil wars experience quagmire, a situation in which belligerents are trapped in fighting? To explain this puzzle, Jonah Schulhofer-Wohl (Leiden University Institute of Political Science) analyses the overlapping strategic interactions between foreign powers and the warring parties. Studying…

Tens of thousands of soldiers and civilians have died as a result of Russia’s invasion of Ukraine in February 2022 and the continuing armed conflict. Many forms of critical infrastructure have been destroyed. Much of this devastation has been caused by weapons that utilise forms of artificial intelligence…

The central question is whether the current regime of international humanitarian law governing the conduct of hostilities in armed conflict is still adequate to deal with modern conflict scenarios, or whether it needs revision or amendment.

COUNTERRR examines domestic responses to jihadist armed groups in Africa, analyzing variation in state repression, community resistance, and the evolution of security across Mali, Nigeria, and Mozambique.

On 17 August 1945, two days after the Japanese surrender that also brought an end to the Second World War in Asia, Indonesia declared its independence. The declaration was not recognized by the Netherlands, which resorted to force in its attempt to take control of the inevitable process of decolonization.…

This dissertation is about Bayesian learning from data. How can humans and computers learn from data?

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The Summer School on International Humanitarian Law is designed by the Grotius Centre Kalshoven-Gieskes Forum on International Humanitarian Law. Registration is now open!

Following its foundation in 1575, Leiden University was quick to incorporate Roman goddess Minerva in its coat of arms. This explains why Rembrandt’s Minerva from 1635 can be seen on the façade of the Academy Building, which has been in use by the University since 1581. This is where, in the Senate…

One of the main challenges in the development of an effective anti-cancer vaccine is the generation of an adequate and directed cellular immune response.

COUNTERRR examines domestic responses to jihadist armed groups in Africa, analyzing variation in state repression, community resistance, and the evolution of security across Mali, Nigeria, and Mozambique.

In this course, you will gain a deep insight into the rules that govern armed conflict, and aim to mitigate human suffering on the battlefield. You will explore the why and how of International Humanitarian Law, followed by the different types of conflict.

The debate about state behaviour in cyberspace may be set in the wrong legal key.

Lecture

Jens Iverson, Assistant Professor of International Law and a Researcher in the Jus Post Bellum Project, defended his Ph.D. dissertation on 21 September 2017.

We have examined sequences from the ligand-binding domain of the nicotinic acetyl choline receptor (nAChR) in 148 vertebrate species. We are in interested in this receptor because the α-neurotoxins of many venomous snakes binds to this receptor in its location at the neuromuscular junction in all ve…

Explore the MSc in International Politics at Leiden University: a one‑year programme focused on international conflict, crisis management, diplomacy and global cooperation.

With an emphasis on developing novel miktoarm star polymers termed PeptoMiktoStars, this thesis leverages asymmetric polymeric polypept(o)ide frameworks to advance their effectiveness in delivering hydrophobic drugs and nucleic acids.

Bas Rietjens and his colleagues researched the Russia-Ukraine war, exploring this multitude of facets and their interconnections.

Jus post bellum, the body of laws and norms governing the transition from armed conflict to peace, has emerged as a crucial issue for international law scholars, governments, and all concerned with building a just and sustainable peace. The Jus Post Bellum Project, funded by the NWO and hosted by the…

Policy Note Insecurity in Burkina Faso – beyond conflict minerals: The complex links between artisanal gold mining and violence

Volume I of The Cambridge History of Strategy offers a history of the practice of strategy from the beginning of recorded history, to the late eighteenth century, from all parts of the world.

To assess the impact of illicit firearms trafficking on gun violence, this research looks at the scope, characteristics and contexts of firearm violence, and also the scope and nature of firearms trafficking in Europe since the new millennium. Nils Duquet, Dennis Vanden Auweele and Marieke Liem created…

The Just Peace Dialogues were a set of meetings for public deliberation of key aspects of building peace in today’s world. The dialogues were held across seven days at the heart of the Just Peace Festival (16 - 22 June 2025).

The Master History (study load 60 EC) offers you the chance to determine a study based on your own particular interests and ambitions.

What contributes to the successes and failures of governance networks in small to medium-sized Western European host cities in attracting International Organizations?