The dark matter of biology: clumps of sugar molecules that, for example, form sugary webs around pathogens. We know very little about them. Wouter Remmerswaal threw all his talent into the challenge – both in the lab and as a modeller – and succeeded. He received his PhD on 12th September.

Kees Waaldijk has worked for many years to map the rights, or lack thereof, of the gay and lesbian community across the world. As he bids farewell to the faculty, those rights are under renewed pressure. How does he reflect on his career?

Ever since the first edition of the Science Run, the Leiden Student Running Association Currimus has delivered the winning team or the fastest runner. Now the event is back, the new batch of students must uphold the honour. The board is also forming a team: ‘During the upcoming training session, we…

‘Countering violent extremism – the international deradicalization agenda’ is the name of the book Tahir Abbas published last month. In this interview the associate professor in Terrorism and Political Violence at ISGA tells about the backgrounds and goals of the book.

Jasper Knoester is the dean of the Faculty of Science. How is he doing? What kinds of things is he doing and what does his day look like? In each newsletter Jasper gives a peek into his life as dean.

On January 1st Jasper Knoester started as our new dean. How is he finding it? What kinds of things is he doing and what does his day look like? In each newsletter Jasper gives a peek into his life as dean.

Secret services are engaging in increasingly extreme forms of cyber espionage. But nobody talks about this. Dennis Broeders knows why and is trying to have an open conversation about new forms of espionage. As Professor of Global Security and Technology, he will give his inaugural lecture on Friday…

When do we define a piece of nature in the city as a park? And when is something a tree or shrub? It may seem obvious, but in scientific literature the definitions vary quite a bit. That makes comparisons difficult. Environmental scientist Joeri Morpurgo looked at the differences and designed a general…

The Young Academy Leiden (YAL) acquired six new members on 1 September. We talked to the new and former chair of this platform for young academics about what they have achieved over the recent period and what is on the agenda for the coming year.

Ever since Nadine Akkerman, Professor of Early Modern Literature & Culture, came across a woman spy in her research, secret agents have kept cropping up in her work. Now there’s Spycraft, a popular history book exploring the espionage techniques used by early modern spies, which she has co-written with…

Over 20,000 students, lecturers, administrators, support staff and many others protested on 25 November against the plans to make billions of cuts to higher education. Students and staff from Leiden University also travelled to The Hague to voice their objections to the disastrous plans.

Since May, Assistant professor BioTherapeutics Lu Su works in our faculty. Although she is still young, she already worked in many different fields and co-operated on two publications in big scientific journals. How did she become so successful and what motivates her to keep researching the possibilities…

Betty de Jonge is a household name in our faculty. As the person behind AskBetty, she knew how to answer every question about Office. Starting this month, she has officially retired.

People from the Dutch islands of Bonaire, Saba and Sint Eustatius say that violence (mainly verbal) is fairly common in families. This is according to research by Leiden University, the University of Curaçao and UNICEF Netherlands. The researchers make recommendations for preventing such violence over…

The Europaeum academic community was awarded the Scaliger medal on 23 September in recognition of its promotion of academic values. Andrew Graham, trustee to the Europaeum and founder and honorary advisor to the Scholars Programme, was presented with the medal by President of the Executive Board Annetje…

A professor from Leiden University, together with a former employee (who is also the professor’s partner), has been guilty of long-term unacceptable and often transgressive behaviour in the form of abuse of power and manipulation. This behaviour led to a culture of fear among staff who were largely…

On the eve of Leiden University’s 450th anniversary, the 1574th and 1575th Honours College students received their honours certificates. In a crowded Scheltema, people celebrated ‘that so many students have had the opportunity to broaden their horizons.’

The night side of exoplanet WASP-43b, to the surprise of astronomers, does not appear to contain methane. It is likely that extreme winds do not allow enough time for methane to form in detectable amounts. This is the conclusion of an international team of scientists, with Leiden and Amsterdam contributions,…

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…

According to Law student Jasmijn van Lochem, you can learn a lot in seven months. For the ‘Onderzoeksassistent’ (Research Assistant) course, part of the Honours College Law, she conducted research on the African Court on Human and Peoples’ Rights in collaboration with Misha Plagis, Assistant Professor…

Neanderthals were able to outwit straight-tusked elephants, the largest land mammals of the past few million years. Leiden professor Wil Roebroeks has published an article about this together with his German colleague Sabine Gaudzinski-Windheuser in the Science Advances journal.

On 24 April 2025, political scientist Pawan Kumar Sen will defend his PhD dissertation, "Transforming Nepal’s Political System: Party Positions and Public Opinion (2004-2012)," at Leiden University. His research examines how Nepal’s major political parties navigated key state restructuring reforms—republicanism,…

Six projects from the Faculty of Humanities recently received grants of up to 750,000 euros from the NWO Open Competition. Researchers involved tell how they will spend this money.

A sense of security plays an important role in the decision to contribute to nature conservation. Stacey Mac Donald conducted four years of research on the influence of social and political changes and the (post) colonial context on nature conservation in the Dutch Caribbean. On 17 May she will defend…

Around lunchtime on 28 October, 18 of our colleagues gathered in a room at the Lipsius, while 22 other colleagues settled in front of their computer for a one-hour update on the development of the alternative Humanities Campus. Dean of the Faculty of Humanities Mark Rutgers and Vice-Chairman of the…

Terrorism, crisis, violence, intelligence, diplomacy, war and peace are topics that are broadly covered in ISGA's research activities. Regularly, ISGA researchers appear in international media to discuss their research expertise. This item offers an overview of non-Dutch and non-English articles and…

From 13 to 16 July, Leiden will host the EuroScience Open Forum (ESOF), the largest multidisciplinary scientific conference in Europe. Lars van Doorn from Leiden Law School will give a presentation.

Athletic achievements, enthusiastic supporters and a beautiful donation for charity: on Saturday 15 April, the Leiden Bio Science Park was the setting for the 5th edition of the Leiden Science Run. All this was accompanied by bright sunshine. ‘What a joy to be part of!’

The prestigious journal Science Translational Medicine has published a study by researchers from the Institute of Biology Leiden (IBL) on a potent new antibiotic that can overcome resistance. ‘The idea was to tweak the original antibiotic and create a next-generation drug’, says Nathaniel Martin, professor…

A basic income would not necessarily mean that people would work less. This is the conclusion of a series of behavioural experiments by cognitive psychologist Fenna Poletiek, social psychologist Erik de Kwaadsteniet and cognitive psychologist Bastiaan Vuyk. They also found indications that people with…

Tensions are rising between Russia and the West. Can an invasion of Ukraine and an international war be avoided? Political scientist and Russia expert Hans Oversloot warns of the consequences if the West chooses a collision course. ‘Offer Russia a dignified exit strategy.’

Famine, bombing of civilians and the almost complete destruction of Gaza. The world looks on at an unfolding humanitarian disaster. Why have our international organisations failed to prevent this tragedy? An interview with Professor Jan Aart Scholte, an expert on globalisation and global democracy.

Vincent Mul is deputy president on the board of The Hague Court of Appeal. Together with Jan Crijns, Professor of Criminal Law and Criminal Procedure, he stood at the cradle of the collaboration between Leiden Law School and The Hague Court of Appeal. ‘By joining forces, we all benefit.’

Even with state-of-the-art technology, it is almost impossible to see: a cosmic neutrino. Yet scientists have managed to image this particle with a deep-sea telescope. And that could help to better understand our universe. Leiden particle physicists collaborated on this ambitious project, published…

Imagine we could do what green plants can do: photosynthesis. Then we could satisfy our enormous energy needs with deep-green hydrogen and climate-neutral biodiesel. Scientists have been working on this for decades. Chemist Chengyu Liu will receive his doctorate on 8 June for yet another step that brings…

The Netherlands is embroiled in a complex nitrogen crisis. Berent Baris wants to use his NitroGenius game to demonstrate the complexity of this crisis.

Smiling faces, a mass dance and a bit of awkwardness: after two ‘corona editions’ of EL CID, the Leiden introduction week is back with a vengeance this year. A total of 3,412 first-year students from Leiden University and University of Applied Sciences Leiden, accompanied by 486 mentors, started EL…

University lecturer Lucien van Beek has been awarded a LUF Praesidium Libertatis Grant. He will use the sum of 75,000 euros to research the thinking of people in ancient and prehistoric times. To do that, he will look for unusual or striking metaphors in the earliest Indo-European languages.

With a self-converted red camper van, biologists and twin brothers Kevin and Marvin Groen go on a nature adventure in Eastern Europe. Together, they search for wild animals, beautiful nature and places to sport. From a long search for a bear in the Slovakian wilderness to the discovery that pelicans…

The West has missed several opportunities to prevent the invasion of Ukraine or, at the very least, to better support the Ukraine, claims Frans Osinga, Professor by special appointment War Studies.

In June 2024 the Faculty of Archaeology welcomed a new Assistant Professor. Dr Alejandra Roche Recinos, originally from Guatemala, will strengthen the Faculty’s expertise on the archaeology of Central America. ‘I want to explore the lesser known archaeology of Southern Guatemala.’

Aafje de Roest turned her hobby into her job. She went from a teenager who enjoyed listening to hip hop music to a PhD candidate who focuses on how Dutch hip hop music shapes the cultural identity of young people in the Netherlands.

The Young Academy has gained a new Leiden humanities scholar as a member. University lecturer Greek language and literature Tazuko van Berkel will be appointed as a member as of March.

Is personal leadership important? Yes, says our university. HR adviser Marieke van den Berg knows from experience just how important it is. She explains why – and what it can mean for your team, and for you personally. And no, it’s not just relevant for managers.

Computer scientist Matthijs van Leeuwen is one of four science faculty members who obtained the Senior Qualification in Education in 2021. What was that like and what drives him? ‘In my own education I would have liked to see more attention paid to the responsibility that machine learning and data mining…

The war in Ukraine is leading not only to human suffering. Ukraine's cultural heritage is also experiencing the consequences of the war: museums are being bombed and 'Russification' in the occupied territories means children no longer learn Ukrainian. Researcher Evelien Campfens was commissioned by…

More than 700 visitors got to know the Science Faculty during the Leiden Science Family Day. People of all ages could enjoy fascinating experiments, tours, interesting lectures, spectacular nitrogen shows and various workshops. It was an informative day with many (future) scientists, amazement and,…

This year, an NWO PhD in the Humanities grant went to Mink van IJzendoorn, enabling him to investigate the disappearance of amphorae. ‘We take means of packaging and shipment for granted, but they are deeply ingrained in our daily lives; they are crucial.’

Multidrug-resistant pathogens and worldwide pandemics are increasing, making infectious diseases more prevalent. To develop new treatments, deeper knowledge of the interaction between bacteria and human cells is required. Ariane Briegel recently became a Medical Delta professor and studies such path…

An international team led by astronomers at Leiden University has shown in laboratory experiments that sulfur can bind with ammonium under icy cosmic conditions and form a salt that sticks to dust and pebbles. The resulting sulfur salt not only helps to explain the mystery of the missing sulfur gas,…