Cotton is the most widely used natural fibre for clothes. But how polluting are our jeans and shirts actually? Environmental scientist Laura Scherer coordinated an international research project on the impacts of cotton. ‘The purchases of consumers in Europe can contribute to water scarcity in China…

A huge shiny aluminium object stands in the middle of the Polderlab in Oud Ade. Are the researchers trying to make contact with extraterrestrial life? Certainly not; they are using the ’Moon landers’ to measure whether innovative forms of agriculture reduce greenhouse gas emissions. Fleur van Duin works…

Connecting worlds, enhancing research and teaching, and providing innovative solutions to complex social issues: that is the idea behind interdisciplinary research. In that respect, a huge amount happened at Leiden University in 2023.

Leiden University is celebrating its 450th anniversary in 2025 with a feast for the eyes, ears and spirit. The anniversary year opens with an extra special Dies Natalis on 7 February. Highlights includes an alumni festival, three exhibitions and a canal concert.

Light, open and green: a description that fits the new, renovated location of the Faculty of Humanities. The official opening of the Herta Mohr Building took place on 8 October, and it has many remarkable features: for example, recycled ‘mushroom columns’, a pedestrian bridge to the University Library…

Bacteria carry countless hidden treasures in their DNA: fragments that could hold the key to new medicines. But how do you pick out the most promising ones from millions of options? ‘Look at the switches that turn genes on and off,’ says molecular biologist Gilles van Wezel.

Martina Vijver has been nominated as Teacher of the Year of the Faculty of Science. She gets this nomination for the course Ecotoxicology she taught in 2022. The 52 students who took the course were hugely enthusiastic, as can be read in their positive reviews. What is so great about this course then?…

The Iran war has pushed up fuel prices and raised concerns about a global energy shortage. How well prepared is the Netherlands? We asked two experts.

The valedictory lecture of former rector magnificus Hester Bijl was buried on Tuesday 12 May in the garden of the Kamerlingh Onnes Building (KOG). Where did this young, and slightly eccentric, university tradition come from?

Alexander van Oudenhoven is the brand-new education director of the master's in Governance of Sustainability. The study has already entered its fourth year and Van Oudenhoven is very enthused. What makes this a special programme and what are his plans?

Researchers at Leiden University have created a unique model that mimics how disease develops after a dengue infection. This 'dengue-on-a-chip' model helps them study the virus more effectively. The timing is crucial, as climate change is causing dengue to spread worldwide.

The interdisciplinary, English-taught minor ‘Violence Studies’ looks at violence from very diverse scientific perspectives. What are the benefits from this approach? Students and lecturers evaluate: ‘This minor’s a goldmine’.

Leiden researcher Anne-Grete Märtson brought together a large number of studies to better understand antibiotic dosing in patients with obesity. The publication in a renowned medical journal has already garnered much positive reactions, Märtson says. ‘It’s high time researchers started sharing more…

Leiden PhD candidate Mona Shahab climbed Mount Everest two years ago to raise money for the education of disadvantaged children in Egypt. She made it to the top and posed there with the University flag. She recently presented the flag to Rector Carel Stolker.

The Vrouw Vennepolder near Oud Ade has been transformed into the Polderlab. Scientists and students from Leiden University, together with farmers and citizens, investigate how to manage peatland in a sustainable and profitable manner. A great opportunity for students to experience how scientific knowledge…

From a vegan community kitchen to a green framework for drug development: sustainability became more visible in everyday campus life at Leiden University in 2025.

Martina Huber, Jacqueline Labra Munoz research Alzheimer's disease. They study ferritine, iron storage in the brain. An inbalance of iron could play a role in this form of dementia.

In the last few days, reports have appeared in the media about security in our buildings. These have raised questions and caused concern. This is to inform you as best we can about the security of our students, staff and visitors, in response to this media coverage. We fully understand there is a need…

Arts and culture

Students at Leiden University believe that their degree programmes should focus more on sustainability. These are the findings of a survey of more than 550 students by Leiden University Green Office.

Last year around 2,000 international students started a master’s degree at Leiden University. To make this possible, there are various grants that these students can apply for. One such grant is the LExS: the Leiden University Excellence Scholarship Programme. Three LExS students tell us about their…

Students who also want to develop their artistic talents can take a year-long art class – Practicum Artium – at the Royal Academy of Art in The Hague. ‘I can express my creativity and am learning to approach subjects in a visual way.’

How are supermassive black holes born? That is the question astronomer Elena Maria Rossi is trying to answer. But how do you investigate something you cannot see?

Koen Keijzer combined three mathematical models into one unified system capable of making meaningful predictions about how cells form blood vessels. This helps biologists studying the chaotic, leaky blood vessels found in and around tumours.

Giulio Barbero and Matthias Müller-Brockhausen did their PhD research at the Leiden University Game Research Lab.

Astronomers who simulate galaxies do not always get the same result, even when they start from identical conditions. New research from Leiden University shows that this is not a flaw, but a consequence of how galaxies behave — and how they are modelled.

PhD candidate Daniël Gomon has developed statistical methods that could significantly improve research in fields like medicine and demography. ‘Mathematicians don’t like unrealistic assumptions,’ he says. Gomon will defend his PhD thesis on 19 June.

The annual conference of the Global Transformations and Governance Challenges (GTGC) interdisciplinary research programme will take place in The Hague on 7-9 June. As a researcher at Leiden University, why should you be there? ‘Nearly every research study has a governance dimension, but academics often…

Since the demonstration over a year ago on the Wijnhaven campus, Leiden University has developed plans and initiatives to create the safest possible work and study environment for our university community. The Executive Board would like to explain what has happened since and what else we can expect…

Two consortia led by Leiden researchers have been awarded over one million euros by the Dutch Research Council and the Ministry of Health, Welfare and Sport to find solutions to antimicrobial resistance.

Music lovers are welcome at this free open-air concert celebrating 450 years of Leiden University, on Sunday 6 July. This special jubilee edition of the Rapenburg Canal Concert will feature a unique orchestra made up of our students, staff and alumni, performing on a floating stage.

Defending your PhD research in front of nearly 300 elementary school students: that was the challenge faced by PhD candidates Jo-Anne Verschoor and Marinka de Willigen during the VUURVLIEGEN competition organised by the Centrum JongerenCommunicatie Chemie (C3). After an exciting competition, the children…

The Dutch Research Council (NWO) has awarded Vidi grants to Leiden researchers.

Lecture

LEGO creations, a clothesline of visions and a journey into the past and the future: just some of the highlights of Uni-vision day, where creatives developed their vision of the future of study.

Leiden biologists have found a mutation in flour beetles that allows them to speed up their development. The study has been published in Nature Ecology and Evolution.

Pesticides can form a toxic cocktail when they occur in combination in surface water. This is the finding of research that Leiden University and the Dutch National Institute for Public Health and the Environment (RIVM) presented on Monday 14 October. The Dutch Ministry of Infrastructure and Water Management…

As the father of a family with four children, he already visited the Hortus regularly. Now Tom Schreuder also comes there for his work. Every day he travels from Lisse by bike. The new Director Operations calls it a ‘perfect match’.

A bacterium hiding from the immune system and picking up bits of DNA from its environment. The result: gaining new traits, such as better protection against antibiotics. Fortunately, we have not found such a damning scenario yet. However, PhD student Renée Kapteijn did find the first clues, which…

Within the same species of butterfly many different wing patterns can occur. How is this possible? According to researchers Ben Wielstra and Emma Berdan, of the Institute of Biology Leiden (IBL), the answer lies within supergenes. A supergene is a part of a chromosome that contains many strongly linked…

The pesticide thiacloprid turns out to be more harmful than previously thought. It can disrupt the lives of freshwater invertebrates and their communities, upsetting the balance and functioning of entire freshwater ecosystems. This was shown by ecologist Henrik Barmentlo and colleagues, their research…

How can we make our cities greener and more people-friendly? Two Campus The Hague projects have secured a grant from the Municipality of The Hague. The researchers and students from both projects are working with city residents to find sustainable solutions to local issues.

Some thirty Leiden students balanced on SUP boards for the Supping for Sustainability Lustrum activity. Together with alumnus Merijn Tinga, better known as the Plastic Soup Surfer, they paddled their boards through the Leiden canals and waterways, fishing plastic waste out of the water.

With the appointment of Dennis Janssen as operational director at the end of last year, the management team at the Observatory is now complete. Janssen has been working at the university for over twenty years, but the faculty and the Observatory are new to him.

The year 2023 saw the earthquake in Turkey and Syria, the Wagner Group rebellion and wildfires and floods as all the weather records were smashed. Our most-read stories were about the climate crisis and the elections: here’s the list.

Should we be growing rice and building materials instead of grass for cows? From invasive crayfish to cultural heritage and groundwater levels: ten graduating students explored the future of the Groene Hart, the rural region just outside the cities of Delft, Rotterdam and Leiden where they study.

Sinds vorig jaar staan er gekleurde pilaren op de universiteitscampus. Met deze ‘Act of Kindness Pillars’ wordt eenzaamheid bij studenten tegengegaan.