From researching plastic pollution to caring for injured wildlife, volunteers play a crucial role in conservation. But much of the valuable knowledge they gather remains unused.

We all know smoking is bad for our health. But we might not have known that the cigarette filters that litter our streets also impact the environment. Esther Kentin is a lecturer at Leiden Law School. She is raising awareness of the University’s cigarette butt problem.

Every Sunday you can help fish plastic and other floating garbage out of the Leiden canals. You can use your own canoe or loan one from Plastic Spotter and join the garbage-fishing fleet. Annetje Ottow, President of Leiden University, was one of the crew on Sunday 4 July.

In the Port of Rotterdam, tiny industrial pellets leak into the environment, causing a form of pollution that’s hard to trace but highly persistent. Three students of the LDE Sustainability Honours Programme took on the challenge to identify sources of this pollution.

Lecture, Studium Generale

The university is launching a campaign to focus extra attention on our smoke-free university locations. The University is using aptly named cigarette barrels to try to show clearly just how many cigarette filters are being saved from the environment. How harmful are these cigarette filters to the e…

Nanoplastics can accumulate in developing hearts, according to a study by biologist Meiru Wang from Leiden University. Her research on chicken embryos sheds new light on how these tiny plastic particles pose a threat to our health.

Arts and leisure, Arts and leisure

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.

Gain the knowledge and skills you need to make an impact on sustainability issues.

Life returned to something resembling normal after Covid but other crises soon took its place. These great challenges are also being felt at the University and our researchers are working on solutions. The nitrogen crisis, problems with young people’s services and an increasingly urgent climate crisis:…

Facility

In recent months, the university has been running the 'Smoke-free university' campaign because of the large number of cigarette waste on and around the faculties. As part of this campaign, gatherings were held in June, September and October to draw extra attention to this waste problem.

External PhD candidate Liselore Tissen has been appointed ambassador for Leiden City of Science. As the youngest member and the only non-professor in the network, she will be working to raise Leiden's prominence as a city of science.

The Dutch Ministry of Education, Culture and Science (OCW) has started a survey to identify the success factors of a strong codetermination culture within higher education institutes. All members of a codetermination council in higher education can participate in this survey until 2 April.

Since 24 March, the Kamerlingh Onnes Building of the Faculty of Law has been full of hundreds of colourful jellyfish. But behind that enchanting sight is a serious message: the exhibition symbolises the loss of biodiversity in the oceans due to climate change.

Amid rising polarisation and discrimination, lawyer and human rights activist Lilian Gonçalves-Ho Kang You wants to show in her Cleveringa Lecture on 26 November how dangerous exclusion is.

Lawyer and human rights activist Lilian Gonçalves-Ho Kang You is the new Cleveringa professor.

Yesterday marked the start of the National Accessibility Week. How accessible is Leiden University for people with a disability? We asked Lucia Langerak, disabled herself and working at the Honours Academy, about her experiences: ‘Significant improvements are being made.’

Brain scans, heart attacks and credit scores: many science applications revolve around data. But how do you mine applicable insights from a mountain of data? In a Bachelor Honours Class, students discover how data science can contribute to their discipline.

Amid the many traditions of Leiden’s 3 October Festival, a relative newcomer is beginning to take hold: the Science Market. At market stalls, the people of Leiden could explore or even participate in Leiden’s research – performing an ‘operation’ in the street, for example.

What better way is there for an alderman to find out where best to put his efforts than to pay a working visit to the university? Hilbert Bredemeijer, Alderman in The Hague for Education, Sport and the Outdoor Space, paid a visit to Campus The Hague on Wednesday 6 October 2021.

Buurtlab 070 is a new Leiden University project in which residents, researchers and students from The Hague work together on climate, sustainability and biodiversity solutions. What do they expect of the lab?

In September 2025 Leiden University hosted a greatly successful academic conference "Care and the Jewish Experience" organized by the Leiden Jewish Studies Network. Among our guests and presenters were academics from many universities, many disciplines and at different stages of their academic caree…

Literature – and films and social media too – helps us understand ourselves and society. That makes literary studies an eternally modern discipline, especially if you dare to combine it with other disciplines, says Nidesh Lawtoo.

Leiden University and four other Dutch universities will appoint 51 PhD candidates to conduct solution-oriented research for and with the African continent.

Haar hele leven wilde de geadopteerde Cindy Huijgen terug naar haar geboorteland China. Inmiddels is de alumnus Chinastudies en Journalistiek en Nieuwe Media er correspondent.

The world is in turmoil. International wars and conflicts have been raging for some time. And political and social developments are causing insecurity, uncertainty and unrest. This has not gone unnoticed within our university community. We have seen protests, demonstrations and other incidents. This…

The LUCAS Institute has both a new Scientific Director and a new Education Director. Stijn Bussels and Esther Op de Beek both commenced their new roles at the start of the academic year.

Are you curious about how the human skeleton works? Discover this and more on 3 October in Leiden and on 4 October in The Hague.

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.’

Tuesday was the opening session of the LDE Bachelor Honours Programme Sustainability. Lecturers introduced themselves, students got to know each other and it was revealed what they will do to contribute to a more sustainable world in the coming months. "I immediately feel like getting started," said…

Taking a Bachelor’s in Security Studies while starting and running two businesses: student Mohamed Sulaiman never stops. But he wouldn’t have it any other way. PLNT The Hague entrepreneurs’ hub is a source of help and inspiration.

What does the University mean for The Hague? And what are researchers and students learning from the city and its residents? The Hague city councillors visited Campus The Hague on 27 September and spoke to administrators and researchers. ‘From Schilderswijk to Benoordenhout: we are a university for…

Alumnus Rennie Roos lives and works in Indonesia. What took him there, what does he do there and what inspires him?

Most people think of waste as something dirty that needs to be disposed of as soon as possible, but Olivia Yun-An Dung's dissertation aims to show that this does not always have to be the case. For this purpose, she focuses on Tzu Chi recycling in Taiwan. There, an army of elderly volunteers has been…

The course Designing Your Life helps students navigate their career pathways. As it turns out, these pathways are full of twists and turns and - as with many journeys - you only make progress once you gather the courage to take the first step.

Debate, Leiden Asia Academy

Study support

Lecture, Studium Generale

Exhibition

450 jaar

Arts and culture

Annetje Ottow is stepping down as President of Leiden University’s Executive Board on 1 September 2025 after almost five years in the role. She looks back at the highs and lows – and ahead to what’s next.