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…

Roderick Bouman is collection manager of the Leiden Hortus botanicus. He keeps track of which plants there are in the garden, where they come from and makes sure visitors can find the right information about them. ‘We are like a regular museum,’ says Bouman. ‘Except that our objects are alive. That…

André van der Laan has been appointed Professor by Special Appointment of Juvenile and Adolescent Crime at Leiden University, a chair established by the Leiden University Fund (LUF) and the Dutch Research and Documentation Centre (WODC). It is the first time that a professorship by special appointment…

Mexico will be electing a new president on 1 July. No matter who wins, there will be little change in the deep political crisis affecting the country. This is the message given by José Carlos G. Aguiar, university lecturer in Latin American studies.

Assyriologists in Leiden have been conducting research into ancient clay tablets from the Middle East for 100 years already. What exactly do these clay tablets tell us? And why is Leiden such a good place to study them?

What if you could watch a CT scan live, instead of analysing the images afterwards? If it is up to the Leiden mathematician Jan-Willem Buurlage, that will soon be a reality. He is developing methods to make the algorithms behind 3D scans faster. Quite a challenge: ‘Just like mathematicians, computers…

From 1 September Erwin Muller will be the new Dean of the Faculty of Governance and Global Affairs (FGGA) in The Hague. What makes him the right person for the job? And what can the Faculty expect in the next few years? ‘Quality and content are crucial. Some growth figures are worryingly high.’

Pharmacist-clinical pharmacologist Robert Rissmann has been appointed Professor of Translational Dermatology. This extraordinary professorship has been created jointly by the Leiden Academic Centre for Drug Research (LACDR) and the Centre for Human Drug Research (CHDR) to strengthen their partnership…

Leiden social and organisational psychologist Carsten de Dreu has been awarded a Spinoza Prize, the top science prize in the Netherlands. We talked to him about his passion for group processes, Leiden University and his dreams for the future. ‘A Spinoza opens up a world of possibilities.'

Cutting down global emissions of greenhouse gases to combat global warming won’t do the trick alone: we also need negative-emissions technology that can capture carbon dioxide directly out of the air. In the prestigious journal Global Environmental Change, PhD candidate Oscar Rueda and colleagues shed…

Hans Slabbekoorn is specialised in animal sounds. On 1 July, he was appointed professor of Acoustic ecology and behaviour. A great honour, according to the new professor. ‘This job never gets boring, whether I am investigating the urban jungle or marine noise.’

Life cycle assessment (LCA) reveals the total environmental impact of products or production processes, and EU rules are going to make this even more important.

From once controversial scientific works and historical bibles, to personal shopping lists and clothing bills. The 17th-century Bibliotheca Thysiana and the archive of the collector Johannes Thysius exhibit both the intellectual and everyday life as it was three hundred years ago. Now a brand-new digital…

Anyone who has taken a walk through the centre of Leiden before might have come across him, an attentive group of tourists gathered around. After studying history, Koen van Toen, or Koen Marijt, started his own business. He now organises historical walks, among other things.

As a student, Thijs Brocades Zaalberg was primarily interested in diplomacy surrounding conflicts. Through research on peace operations and subsequently the fight against guerrillas, he became increasingly involved with the most violent aspects of colonial warfare. Per 1 September 2024 he is appointed…

From the discovery of exoplanets to the hunt for extraterrestrial life. At the Astronomy Gala on 17 December in the concert hall in Leiden, astronomers looked back, but above all ahead. With King Willem-Alexander as guest of honour.

Two terrifying yellow eyes stared at eleven-year-old Francis Lesilau. In the evening light they changed colour: green, amber, back to yellow... The lion had just grabbed one of his camels and now turned to number two. For a moment Francis was nailed to the ground, then he ran towards the predator, screaming.…

Donald Trump was sworn into his second period as President of the United States on 20 January 2025. Since then, the Trump administration has raised alarms for people around the world who are concerned over what this will mean for the current geopolitical landscape. Join a panel of experts to discuss…

Het strategisch plan van de faculteit wiskunde en natuurwetenschappen (FWN) werd gepresenteerd tijdens de opening van het academisch jaar 2023-2024.

Swarms of drones, pedestrians or the cells in your body. Those are all examples of active matter: materials whose building blocks can move autonomously. That’s what Luca Giomi studies. Giomi has been appointed Professor of theoretical physics in the area of soft matter and biological physics at the…

It's a race against time for Charles Jeurgens, Leiden Professor in Archival Studies. He is investigating how the colonial authorities created the archives in the National Archive in Jakarta. ‘The acidic paper deteriorates rapidly in this hot and humid climate.’

The research Early Pleistocene human occupation at the edge of the boreal zone in northwest Europe published 8th July 2010 in Nature is part of the Ancient Human Occupation of Britain (AHOB) project, in which the Faculty of Archaeology of Leiden University is involved.

How can rare and expensive materials be used more efficiently to produce cleaner and cheaper fuel? Under the guidance of Marc Koper, Professor of Catalysis and Surface Chemistry, international teams of scientists have published 3 articles in Nature Communications.

Rogier Hartendorp is professor by special appointment of social effectiveness of justice at Leiden University and a judge at The Hague District Court. So, the perfect person to liaise between our faculty and the Court. We asked him some questions about this role.

‘A woman with a mission’. In this honourable way, Dean Geert de Snoo described computer scientist Felienne Hermans at the official opening of her new research group Programming Education Research Lab (PERL). He is right: Felienne has a very important mission. With her new research group, she will do…

Jelle van Buuren, Assistant Professor at the Institute of Security and Global Affairs, appeared as guest on VICE to discuss the usefulness of recent ban on QAnon.

At the beginning of March 2020, the Dutch Taskforce for Applied Research (SIA) awarded Daan Weggemans of the Institute of Security and Global Affairs a research grant. The Taskforce is part of the Netherlands Organisation for Scientific Research (NWO).

On 8 February 2016, Dr Jennifer Tour Chayes, Director of Microsoft Research in Boston and New York, will be presented with a Leiden honorary doctorate by Frank den Hollander, Professor of Probability Theory and Statistical Physics.

Hans Slabbekoorn researches animal sounds and the effect of the noise we humans make on these animals. He is also committed to making his discipline more diverse.

In November a new extracurricular programme will begin: the Impact Challenges. Students will work together in small groups to solve problems, put forward by partner organisations. In this way, they train their practical skills and make a contribution to society.

As Director-General of the ESO for the past ten years, Leiden University astronomer Tim de Zeeuw had ‘the best astronomy job in the world’. Back at the Leiden Observatory, he is focusing on the first 3D map of the Milky Way.

PhD students Alex Brandsen and Wouter Verschoof-van der Vaart are both doing a project within the university’s Data Science research programme. The are introducing terms like ‘text mining’ and ‘advanced machine learning’ into archaeology. ‘These techniques will make archaeology more efficient and ch…

The Faculty Board and the Institute of Private Law have agreed to combine the disciplines of child law, international children’s rights and health law into one Department of Child Law and Health Law.

Have you considered including the Leiden University Fund in your will?

Professor of Fungal Genetics and Biotechnology Arthur Ram explains how fungi can help us be more sustainable.

What is it like to work in the consulting industry? Twenty-five students from the bachelor programme Informatics & Economics visited the consulting firm BearingPoint, where they innovated the business model of a telecom company.

Martijn Manson became programme director for the Master’s in Pharmacy this month. He is a pharmacist as well as a lecturer and researcher at the LACDR (Leiden Academic Centre for Drug Research). ‘LUMC and LACDR share the responsibility for training the pharmacists of the future.’

Bring together young academics from all disciplines: that, in a nutshell, is the mission of Young Academy Leiden. And this fledgling organisation is already proving to be somewhat of a success. This is evident at the first Young Academy Lunch at the Faculty of Social and Behavioural Sciences.

How will future technological developments influence our everyday lives? This is the key question during the Brave New World symposium on 2 and 3 November.

The free AI and Ethics course (in Dutch) is available online to anyone who wants to find out more about the ethical implications of artificial intelligence. One of the eight experts featured in the course is Professor Reijer Passchier. ‘Artificial Intelligence is spreading so fast and has such an impact…

Between 11 and 13 September 2025, the ESIL Annual Conference took place in Berlin, Germany. This year's conference unfolded on the theme 'Reconstructing International Law', attracting an unprecedented number of legal scholars from all over the world.

Leiden alumnus Makoto Yoshida from Japan studied Dutch history and politics from 1996 to 1997. Now he is back in Leiden with his wife who is currently a student at the Faculty of Humanities. Some things still surprise him. 'Everyone at university uses first names, which was - and still is - unacceptable…

He is the chair of the Faculty Council, Director of Education at the Institute for Philosophy and a Fellow of the Leiden Teachers’ Academy, and was recently appointed for three years as chair of the Humanities Lab. This is the Honours College programme of the Faculty of Humanities for students of all…

It is a known trait in humans to anchor innovations in the past, so as to make new developments easier to accept. It is an aspect of humanity that can also be spotted in classical and prehistoric times. Archaeologist Daniel Turner will investigate the anchoring of monumental building in Greek Prehistory…

Jelle van Buuren bespreekt de link tussen radicalisering en psychiatrische problematiek.

Researcher Max van Duijn and PhD student Bram van Dijk apply language models to stories told by children to investigate empathy. For this research, they received the Best Paper Award at the Computational Natural Language Learning Conference in Singapore.

There was a lot of interest. In front of nearly a hundred researchers, supporting colleagues and Martijn Ridderbos, the Vice-Chairman of the Executive Board, Lotte van Dillen, Research Director of Psychology and Saskia Goedhard, Director of Humanities Operations jointly opened the new lab with a classic…

Next year in July Leiden University will receive around 1,500 Asia experts from around the world, for the 11th International Convention of Asia Scholars (ICAS 11). This is the world's biggest Asia meeting. Besides an academic programme, the convention also offers an extensive cultural programme for…

Rik van Gijn was appointed professor of Ethnolinguistic Vitality and Diversity in the World from 1 December 2024. He is keen to use the position to set up research on language vitality. ‘People almost never give up their mother tongue entirely voluntarily.’

Maarten Mous, Professor of African Linguistics at Leiden University, looks back on the 50th edition of the Colloquium of African Languages and Linguistics (CALL) and explains why this birthday was a celebration like no other.