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Valerie de Koeijer Assistant Professor in Conflict Resolution and International Organization
Faculteit Governance and Global Affairs

Conflict hits schooling hardest where children are the target News - 17 June 2026
Education systems cannot function if children do not feel safe. Protecting schooling in conflict settings therefore goes beyond rebuilding infrastructure. It requires addressing the threats that keep children out of classrooms. Political Scientist Roos van der Haer and her colleagues show the impact…

A platform for a complex conflict: ‘Friction is good’ News - 17 February 2026
Yousef Sweid was called a ‘stinking Arab’ in the sandpit at his Jewish kindergarten in Haifa. In a packed lecture hall, the Palestinian-Israeli actor performed a powerful excerpt from his show ‘Between the River and the Sea’.

The role of chemical weapons in the Ukraine conflict News - 23 December 2024
Anneleen van der Meer discusses Russia's alleged use of chemical weapons in Ukraine in an article for The Conversation.

Give peace a chance: the way conflict can be eased, according to social psychology News - 1 February 2024
How to reduce aggression when two parties are at odds? PhD research by psychologist Lennart Reddmann's shows that it can help to offer them a peaceful alternative. However, the attacking party benefits the most from such a solution.

PhD Ceremony Mees Vergouwen – solutions for conflicting tax regulations News - 6 April 2023
That the tax authorities are allowed to impose taxes is widely known. What is less well known is when the tax authorities must impose taxes. And what to do when one set of regulations requires the tax authorities to impose taxes while other regulations prevent them from doing exactly that? Vergouwen’s…

Innovative research on impact of violent conflicts on food security in Chad News - 13 December 2021
Violent conflicts and civil wars in Chad impede most rural households' access to food security, agricultural activities and access to essential services such as health care. In her dissertation, Nakar Djindil Syntyche denounces this issue. She obtained her PhD on 24 November.

operations have become increasingly important in Israel-Palestine conflict’ News - 16 April 2024
From 1967 to 1982, the United Nations undertook several peacekeeping operations in the Middle East. In his thesis from the Institute for History, Diego Salama examines how these operations were connected and their impact on the region.

New Special Chair Bas Rietjens with focus on intelligence in conflict situations News - 1 February 2022
Prof. dr. ir. Bas Rietjens of the Dutch Defense Academy (NLDA) has been appointed Professor by special appointment Intelligence in War and Conflict at Leiden University’s Institute for Security and Global Affairs (ISGA). The appointment of Rietjens is the result of a more intensive collaboration between…

Valerie Sticher wins Cedric Smith Prize 2021 News - 14 September 2021
Valerie Sticher has been awarded the Cedric Smith Prize 2021 of the Conflict Research Society (CRS) for an article she wrote as a part of her dissertation at ISGA last May. The Cedric Smith Prize is awarded annually to the best article or thesis chapter in peace and conflict research by a PhD student.…

How gas conflicts between Ukraine and Russia were the precursor to war News - 19 November 2024
The war between Ukraine and Russia is playing out not just on the battlefield but also on the geopolitical playing field of gas. Conflicts at the start of this century about this energy source were, says PhD candidate Ilia Barboutev, a precursor to today’s war.

Special lecture Jan Vleggeert: 'A citizen's perspective on conflicts of interest' News - 30 June 2022
When Professor of Tax Law Jan Vleggeert delivered his inaugural lecture in Leiden University’s Academy Building on 30 October 2020, only 30 people were allowed to attend due to coronavirus measures. On 10 June 2022, Vleggeert was therefore given the opportunity to deliver a lecture to a much larger…

Video labs and narratives of future conflicts: two lecturers receive a Comenius Grant News - 24 June 2025
Lecturers Marjo de Graauw and Malte Riemann have both received a Comenius Teaching Fellowship.

Everyone has the right to food security, in peacetime and during armed conflict News - 3 September 2025
Food security touches upon human rights, international law and sustainable development. These frameworks are not separate worlds but deeply interconnected; something that becomes painfully clear in times of climate crisis, armed conflict and inequality.

Gawthorpe on the Conversation: ‘US and allies not prepared for protracted conflict’ News - 10 March 2026
University lecturer Andrew Gawthorpe comments in an article on the Conversation on Trump’s attack on Iran.

Violations of law during armed conflicts should be investigated – also by Russia News - 12 May 2022
The chance that it will do so is about zero, but Russia is legally obliged to investigate violations of law during the war in Ukraine. States that enter into an armed conflict often deny liability, but under international humanitarian law and human rights they are obliged to investigate their military…

Making room for conflicting feelings will help police promote diversity and inclusion News - 13 November 2024
Diversity and inclusion within the police creates opportunities but also meets resistance. Professor by special appointment and former police officer, Saniye Çelik, emphasises how ambivalent feelings about D&I are essential to the learning process and can lead to informed decisions and real change.

‘Deprived of Liberty, Denied Justice: Double Jeopardy for Children in Conflict Situations in Africa’. News - 26 June 2024
New Report Launched by ACPF with the support of the Department of Child Law and Health Law