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Probing complex problems


Combining different disciplines, Leiden University researchers work together to formulate innovative solutions to societal problems. Below is an example from the field of politics and governance.

Overview research dossiers

Governance solutions for global challenges

Issues such as climate change, the depletion of natural resources or social inequality are too complex to be addressed from a single scientific discipline or by a single country.  Leiden University has the expertise to bring the resolution of these enormous problems a small step closer.

Cause and solution
Some phenomena cannot be studied in isolation. They are linked within a chain of cause and effect that spans the whole world. As an example, environmental pollution leads to climate change that causes the worst drought in southern Africa in 112 years. Harvests fail and cattle die of starvation; society becomes disrupted. All this leads to a massive wave of migration. The arrival of refugees fuels simmering discontent in European countries and creates a political earthquake.  It takes a very diverse body of knowledge to be able to reverse these kinds of developments, knowledge ranging from chemistry, biology and environmental sciences to anthropology, political science and public administration. What constitutes responsible nutrition that will keep people healthy without overburdening the planet? Which environmental problems should we tackle first? How can we provide a factual basis for the debate on employment migration? What new forms of international discussion are most effective? How can we share knowledge fairly? Leiden University brings together a diverse raft of scientific expertise to find answers to these questions. What makes Leiden uniquely placed to achieve this is the centuries-old Leiden tradition of studying distant countries, languages and cultures, in particular China, Africa, the Arab world and the Middle East. Leiden is an international hub of knowledge and contacts. 

Leiden University in The Hague
Besides Leiden’s international focus, there is also a local dimension. Much of the University’s research on global problems takes place in The Hague, in the heart of the ‘international city of peace and justice’.  With its International Criminal Court and its International Court of Justice,  ministries, multinationals, embassies and numerous international conferences, The Hague is an ideal breeding ground for research and teaching on such issues as security and threat, as well as other global challenges.  Judi Mesman, Dean of Leiden University College The Hague, and her academic staff are frequent discussion partners for diplomats, international lawyers and industrialists. Mesman is convinced that academic research relevant to current policy can only be truly effective if every step is discussed thoroughly with experts from the field of practice. ‘That increases the likelihood of scientific insights actually being applied,’ in her opinion. ‘And in the course of our research, we are also educating the problem resolvers of the future, young people who take the world’s problems to heart and who will shortly also have the instruments at their disposal to be able to do something about them.’

Healthy food, healthy world

What does it mean to eat healthily and responsibly? This question is gaining a new urgency now that in many countries undernourishment is being overtaken by diseases of affluence, such as obesity, and we are also becoming more aware of the environmental impact of our eating habits. It’s time to take a good look at our nutritional guidelines.

Risks unevenly distributed
Prosperity is rising in countries such as India, Mexico, Nigeria and Guatemala, where a growing middle class has more financial freedom. The inhabitants of these countries are now attracting the same health risks as people from the western world. The consumption of convenience food can lead to obesity, cardiovascular diseases, cancer and diabetes, while at the same time there are still very poor groups in these countries, who are malnourished or whose food puts them at risk of infectious diseases such dysentery, thyphoid fever or hepatitis. Health risks are shifting, but they are still unevenly distributed, both over the world and within a society. This is also true of rich countries, where nutritional problems are more prevalant among disadvantaged groups.

Is taxing sugar effective?
Assistant professor Jessica Kiefte studies how eating habits and health are related in different parts of the world. Her research combines population studies - in which people’s lifestyles are tracked over decades – with medical data on the same group. She also explores which measures encourage people to eat more healthily. Measures that have already been implemented, such as adding iodine to salt and bread and adding vitamin D to dairy products and margarines, have already proven their

Fast food is becoming steadily more popular in countries such as India, Mexico, Nigeria and Guatemala.

Fast food is becoming steadily more popular in countries such as India, Mexico, Nigeria and Guatemala.

effectiveness. But some new measures that are being proposed are disputed, such as a sugar tax, or enhancing bread with folic acid. To give these discussions a factual basis, Kiefte is looking for certainty about which measures do or do not contribute to health.

Updating food guidelines
Dietary guidelines based on scientific evidence, popularly referred to as the ‘Five-a-day’ (UK and the Netherlands), the food pyramid (Belgium, Italy) or colourful posters with ‘good’ and ‘bad’ food (Sweden). Guidelines in these forms can be an effective way of encouraging people to eat healthily. But are they still correct? That’s one of Kiefte’s questions.  ‘Guatemala, for example, still stresses the consumption of animal products such as fish, meat and eggs, in its guidelines, but this dates from the time when there was a bigger risk of malnourishment. These days, over-nutrition is more likely to be a problem. This is something we’re exploring and we will be suggesting some modifications to the advice. What we are ideally aiming for is to reach vulnerable groups of people, for whom healthy eating is almost a luxury.’

Environmentally aware eating
A new factor is that nutritional guidelines today are not just about health. ‘You can recommend that people eat fish,’ says Kiefte, ‘but if over-fishing means that the seas are becoming empty, that’s not such good advice.  Eating a piece of steak also has its drawbacks, because livestock farming puts a heavy burden on the environment.’  Kiefte works increasingly often with environmental researchers like Paul Behrens, Assistant Professor of Energy and Environmental Change, so that nutritional advice is assessed not only on its effects on human health, but also on its impact on the environment. ‘Obviously, a nutritional guideline that isn’t good for our environment, also isn’t good for our health.’

A Dutch fishing trawler at work 50 km off the coast of Mauritius.

A Dutch fishing trawler at work 50 km off the coast of Mauritius.

What to focus on for a clean environment?

The earth has more than 7 billion inhabitants, all of whom leave behind traces of pollution. However, not all forms of pollution have the same harmful effect. Leiden scientists help determine where we should put our priorities.

Insidious effect
Thirty years ago, the sewers of Amsterdam were simply emptied into the city’s canals, but today these same canals are so clean that every year several thousands of people swim in them for charity.  Overall, we are becoming more and more successful at protecting the environment from massive flows of waste.  The biggest challenge now is to address the more subtle effects of small doses of waste in the environment that can have an insidious impact on undermining the health of different species of animals.

Stress in the delta
Environmental toxicologist Thijs Bosker conducts research on the impact of foreign matter on ecosystems. His main interest is dynamic systems, such as deltas. In a delta, fresh water and salt water come together and the water conditions, such as oxygen levels and temperature, are subject to continuous change. The organisms that live in the delta are constantly having to adapt to new circumstances. ‘Places where a river flows into the sea are important both ecologically and

The Rijn-Maas delta, here shown at the Maasvlakte near to Rotterdam, is a good example of an area where there is a high likelihood of a clash between economic and ecological activities.

The Rijn-Maas delta, here shown at the Maasvlakte near to Rotterdam, is a good example of an area where there is a high likelihood of a clash between economic and ecological activities.

economically,’ Bosker explains. ‘There is a wide variation of animals and plants, but river mouths are also where cities are often located. These cities cause pollution, which puts that already dynamic system under even more stress. We want to know how organisms cope with these issues. It’s a big challenge, because it’s difficult to model the dynamics of this type of ecosystem in the lab. These kinds of systems are something of a black box for science.’

Help from holidaymakers
Bosker researches new types of environmental pollution. He is mapping how many tiny particles of plastic enter the global environment. He is helped in his research by holidaymakers: they send samples of sand from all over the world to Leiden so that Bosker and his team can check how many ‘microplastics’ wash up in places as far apart as Iceland and Zanzibar.  The next step is to explore whether these plastic particles pose a risk for the flora and fauna. Bosker is also interested in the impact of pollution on the reproduction of different organisms. In the Gulf of Mexico, for example, he studied the impact the disaster with the Deep Water Horizon drilling platform had on the local fish population.  In Canada he works with paper manufacturers and local governments to study the effect of endocrine disrupters in their waste water on reproduction in fish.

Volunteers send in samples of sand from their holiday destinations.

Volunteers send in samples of sand from their holiday destinations.

‘If environmental pollution leads to dead fish floating in our rivers of streams,  that effect will be highly visible,’ Bosker says. ‘Fortunately, we are seeing this less and less. But what about if fish can no longer reproduce because their hormone system is disrupted, or if they can no longer escape animals that prey on them because their nervous system is impacted? These are the kinds of indirect environmental effects that are at the heart of our research. I believe it’s important to have a good understanding of all these risks, although it’s almost an impossible task to clean up all environmental waste; it would cost far too much. But if we understand the potential effects of all these substances in differing circumstances, then we are able to set priorities to limit environmental damage or even to prevent it. That way, we can better protect the environment, and that’s something I’m keen to contribute to.’

Global Microplastic Project

Understanding labour migration

To ensure that the growing global flows of labour migrants are guided correctly, we need knowledge. Why do people leave home, why do they go to specific countries, and how can that choice be influenced? And what are the consequences of their leaving for the people who stay?

Welfare state unattractive
Leaving your village, region or country and trying your luck elsewhere is an age-old and worldwide strategy for achieving prosperity and personal fulfilment. In a globalising world, more and more people are choosing this route. Political economist Alexandre Afonso is fascinated by the issue of how a country’s attractiveness for migrants is partly determined by the socio-economic policy it pursues. Afonso’s research has produced some surprising results. ‘Politicians often claim that a generous welfare state such as the Netherlands attracts immigrants like a magnet,’ he says. ‘But the figures show that this isn’t the case. Quite the opposite, in fact: the relationship is inversely proportional. The more generous the welfare state, the smaller the number of 

migrants. And it’s easy to understand why. A generous welfare state needs to have a high tax rate, so it’s expensive to hire workers in countries like Sweden, France or the Netherlands. Employers would rather mechanise their processes or increase labour productivity. In England, on the other hand, the situation is different. You even see people there walking around with boards telling you the way to the nearest McDonald’s. That says something about the price of labour. A country like that is more attractive for migrants, because there are more low-paying jobs.’

Because labour is cheap in the UK, people are hired to stand around with advertising signs.

Because labour is cheap in the UK, people are hired to stand around with advertising signs.

People back home in Africa
Cultural anthropologist Caroline Archambault researches the sources of migration flows. She wants to know why people leave home and what it means for the people who stay. ‘In Tanzania, the men leave the countryside to find work in the cities. Often their wives choose to remain in the villages with their children as they find rural life safer, more fulfilling and empowering.’

In Kenya, Archambault saw that young Maasai people are leaving their villages to attend school in the cities. The traditional pastoral life didn’t require a school education. But drought, ecological exhaustion and privatisation of land are making that career choice less attractive. Over the last ten years or so, many young Maasai people have therefore been preparing for a different professional life. A striking aspect is that the community back at home tries very hard to maintain ties with the young people. Thus important rituals – marking the transition to a new stage of life, for instance – are drastically shortened and modified. They are often held during the school holidays, just like weddings and other celebrations. Conversely, the young people who emigrated also make sure the ties stay strong, for example by using Facebook for social control. Archambault has found that if a village elder abuses his power, he will be reprimanded by these young migrants via Facebook. ‘That means loss of face, so it works!’

Back to the facts
Academic research on migration often yields surprising insights. Researchers are trying to reintroduce the facts into a highly politicised debate, so that it can be conducted more efficiently and effectively.

Maasai women speaking at a political rally

Maasai women speaking at a political rally

Sustainable solutions

Knowing how to resolve global problems is one thing, but how do you make sure that it actually happens? That’s the real challenge, because there are powerful movements everywhere that want to reconstruct the walls of nation states. In an attempt to resolve this issue, Leiden researchers are experimenting with new forms of consultation.

Making institutions more inclusive
The time is long past when a handful of national states took decisions in the seclusion of the Security Council, says Professor of International Relations Madeleine Hosli. ‘Everyone throughout the world is linked to one another and everything moves so fast. Problems can only be addressed within a complex and broad network. It’s important that governments are part of these networks, as well as international organisations, regional interest groups and NGOs, to name just a few.’ Hosli and her colleagues are studying how these networks function most effectively. Their findings indicate that some international institutions are lagging behind. ‘The UN Security Council, for example, still represents the victors of the Second World War, and it’s questionable whether it functions as it should. Without the veto of Russia and China in the Security Council, we may not have witnessed the horrors in Syria that we are now faced with. One question we need to answer is how you can shape new, more inclusive institutions where emerging countries such as India or Brazil can have a place.’

Is it time to reform the UN Security Council?

Is it time to reform the UN Security Council?

A crisis can help!
An alternative form of consultation that’s becoming increasingly popular is the round table discussion, and there are many of these already in existence. They are international and can look at a vast array of topics, such as the sustainable production of soya, palm oil, beef or biomaterials, for example.  All the parties concerned sit around the table together. The aim is to determine sustainability standards through discussion that will result in reducing the pressure on the environment. Public administration expert Gerard Breeman carries out research on how these round tables function and on dialogues in which many parties participate. ‘What we see is that the participants learn a lot from one another, even if they do not hold the same opinions. Another noticeable finding is that a crisis forces the parties together. We saw that, for example, with the outbreak of the Zika virus and bird flu, and we see it too with floods.  Such calamities as these appeal to people’s desire to work together to put things right.  It generates a lot of energy when we roll up our collective sleeves and work together. But at some point the crisis ebbs away and then we return to an ‘every man for himself’ situation.  We have to find mechanisms to hold onto that feeling of togetherness for longer. That could be something like a common problem definition maybe, or a joint budget.’

Mutual trust
A sustainable policy is not just about sustainable content, according to Breeman. Sustainable also means that the policy remains in place even if the issues at stake are already three hypes further. It calls for political courage. And sustainable policy is impossible without sustainable relations and mutual trust. Then you have the question of how you can build up this trust. Breeman believes it’s vital for all parties to continue their dialogue. They need to develop an understanding of one another’s viewpoint, by means of a role play, for example, or formulating a shared goal and keeping on referring back to it, and by really looking at and accepting the facts, not escaping into ever more research, as so often happens. ‘You can have a fantastic plan, but if the people who have to put it into practice don’t trust one another, the plan will go nowhere. That’s why mutual trust is one of the focal points of my research.’

Knowledge as world heritage

Researchers have the whole world as their work area. Dutch researchers collaborate with Chinese, Australians give lectures in Lithuania, Koreans move to America and back. Who can contribute to academic knowledge, who benefits from it and who pays for it? A fair and effective system for this has not yet emerged.

Finding a balance
‘Knowledge is like the environment,’ says Maarja Beerkens, Assistant Professor of Public Administration. ‘It is precious heritage, which has been built up over the years and which we have to protect, share and pass on to the next generation.’ But how do you organise that? The possibility of protecting intellectual property is a motor for the economy. It encourages companies and publishers to invest in developing and distributing new knowledge. Yet on the other hand, it’s in everyone’s interest if knowledge is shared. Where does the balance lie? This is one of the questions that Beerkens studies in her work. ‘You can ask what a fair balance is from the point of view of ethics,’ she explains, ‘or you can research analytically what works out best for the common good.'

Payment wall
People increasingly feel that the balance is wrong. In a globalising economy, there is strong pressure to enforce respect of intellectual property worldwide. People therefore have to pay for academic papers. Someone in a poor part of the world usually won’t be able to afford them, and won’t always have access to a

university library. So a doctor in Venezuela can be deprived of information that actually exists and could perhaps be used to cure a patient, because it’s protected behind a payment wall. This payment wall also means that many large groups around the world are excluded from the academic world. They can’t contribute anything and can’t build on existing knowledge. This is a loss for the rich countries too, as it deprives them of relevant data. The call for ‘open access’ to academic knowledge is therefore widely supported.

Scientist in Africa makes use of Open Access sources.

Scientist in Africa makes use of Open Access sources.

New optimism
Beerkens is exploring new organisation forms for managing academic knowledge, which result in fewer people being excluded. ‘One country alone can’t change the system,’ she says. ‘The interests are just too intertwined for that. We can only tackle this problem with global governance. UNESCO, the OECD and the European Commission can also see this, and they’ve taken some steps. But it’s a terribly slow process. And there are so many different parties involved: governments, universities, publishers, libraries, research funders, patent offices, international organisations… hundreds.’ Beerkens is enthusiastic about an alternative model, which is more rooted in academic practice itself. Worldwide academic communities of researchers with the same interest are crucial in the model. They could organise themselves, publish their own journals and cut the ties with commercial publishers. ‘It’s still a very new plan,’ emphasises Beerkens. ‘The way the academic world is organised at the moment is still quite chaotic. But there’s certainly a new optimism.’

Atrocities: when does the world intervene?

If we want to solve global problems, we need to know about both the theory and the practice. How does the international community make decisions about military intervention, for instance? Why is it such a complex process? Professor Herman Schaper has represented the Netherlands at the United Nations and NATO. He gives his colleagues and students a peek behind the scenes of international decision-making.

Wrangling over military intervention
Various war zones around the world issue the same cry for help. Why is it so difficult for the international community to take action? Not only has Professor Herman Schaper acquired considerable knowledge of this field, as a diplomat he was closely involved in international decision-making.

Military intervention is one of Schaper’s fields of expertise. ‘The international community constantly wrangles with the question of when military intervention is justified. In 1648, at the end of a long religious war in Europe, the principle was established that a country is sovereign and other countries may not interfere in the domestic affairs of a state. The development that events in one country affect another one began to gain currency, and this can justify intervention in a sovereign state if the situation has become completely out of hand.’

Responsibility to Protect
An important modern tool that authorises military intervention under international law is a UN Security Council resolution. ‘In 2005 the UN took a step further in establishing grounds for such a resolution when it established the Responsibility to Protect (R2P) principle: the responsibility of a ruler or state to protect its people from genocide, ethnic cleansing, war crimes and crimes against humanity. And if the state of such a country fails to protect its people from such crimes or violations - or worse still is responsible for them -  the international community can intervene. In a considerable number of cases since, R2P has led to the unanimous decision to intervene, in countries such as Libya and the Côte d'Ivoire. But R2P is the subject of much discussion too. In recent years Russia and China have expressed opposition to R2P, arguing that the Security Council makes improper use of this principle to topple governments.’

Player on the world stage
Alongside theoretical knowledge, Schaper possesses a wealth of practical experience. When he was Permanent Representative at the UN in New York from 2009 to 2013, the Netherlands was not a member of the Security Council. ‘But in such times a small country can still be a player on the world stage. Groups of country representatives regularly leave the city for informal brainstorming sessions about military and other interventions. Depending on your position, you as a country can sit at the negotiating table and brainstorm in small groups. If you as a country have good ideas about and experience in a particular area and show that you are doing something – such as providing 

money or military support – you can define problems and suggest solutions. Very good results have ensued from such sessions, such as the birth of the Millennium Goals and, further back, the peacekeeping missions. Although there are many such missions now, the term does not occur in the original UN Charter. A small country can also play a role as a member, or even chair, of what is termed a group of friends for certain topics. The Netherlands is chair or co-chair of the groups of friends on R2P and food security. And finally the Netherlands obviously plays a role as a member of the EU, which in many cases acts as a single block.’

Herman Schaper (right) on a working trip to the Uruzgan Task Force Source: Wikipedia

Herman Schaper (right) on a working trip to the Uruzgan Task Force Source: Wikipedia

Schaper disseminates his knowledge in his teaching and lectures. He is also a member of the Senate of the Dutch Parliament on behalf of the D’66 Party. He says that in some ways this post is comparable with his work as Permanent Representative. ‘We recently met politicians and experts on European security. There might be a European Defence Union in which countries work together, share technology and carry out joint military missions. We use the knowledge that we acquire here for discussions within the party as well as with other groups.’


  • Judi Mesman
  • Gerard Breeman
  • Jessica Kiefte-de Jong
  • Thijs Bosker
  • Anar Ahmadov
  • Paul Behrens
  • Beatrix Campbell
  • David Ehrhardt
  • Ed Frettingham
  • Kai Hebel
  • Paul Hudson
  • Jay Huang
  • Joris Larik
  • David Zetland
  • Brandon Zicha
  • Dimiter Toshkov
  • Sarah Giest
  • Jaroslaw Kantorowicz
  • Sinisa Vukovic
  • Rob de Wijk
  • Herman Schaper
  • Alexandre Afonso
  • Caroline Archambault
  • Madeleine Hosli
  • Maarja Beerkens

Judi MesmanProfessor Diversity in Parenting and Development / Dean LUC

Topics: Diversity, parenting, child studies

+31 (0)71 527 3482

Gerard BreemanAssistant Professor

Topics: Comparative public policies, trust, politics of attention, policy agenda setting, trust, food governance and European Union policies

+31 (0)70 800 9373

Jessica Kiefte-de JongAssistant Professor

Topics: Epidemiology, life-course health research, nutrition and health, public health

+31 (0)70 800 9473

Thijs BoskerAssistant Professor

Topics: Ecotoxicology, environmental sciences, mutiple stressors, reproductive biology, risk modelling

+31 (0)70 800 9475

Anar AhmadovAssistant Professor

Topics: Political Economy of Development, Natural Resource Governance, Migrant Political Behavior, Political and Economic Inequality, Conflict Studies, Impact Evaluation

+31 (0)70 800 9470

Paul BehrensAssistant Professor

Topics: Renewable Energy, Climate Change, The Energy Transition, Sustainable Food Systems, Energy Policy, Physics

+31 (0)70 800 9332

Beatrix CampbellAssistant Professor

Topics: International Relations Theory, EU Integration Theory, EU Foreign Policy Russia, EU’s Eastern Neighbourhood, Research Methods in International Relations

+31 (0)70 800 9310

David EhrhardtAssistant Professor

Topics: International Development, Conflict Studies, Africa (West Africa and Nigeria in particular), Politics of Ethnicity, Religion and Class

+31 (0)70 800 9313

Ed FrettinghamAssistant Professor

Topics: International Relations, Security Studies, Theories of Security, Religion in International Politics

+31 (0)70 800 9477

Kai HebelAssistant Professor

Topics: inter-state war, diplomatic solutions to international conflict, transatlantic relations, US foreign policy

+31 (0)70 800 9948

Paul HudsonAssociate Professor

Topics: Environmental change, geomorphology, physical geography, historic landscapes, hydrology, lowland rivers, Mississippi river

+31 (0)70 800 9330

Jay HuangAssistant Professor

Topics: Cultural governance, Foucault's houghts, human security, international politics, national identity, theories of nationalism

+31 (0)70 800 9596

Joris LarikAssistant Professor

Topics: Comparative law, EU foreign policy, EU law, global governance, international law

+31 (0)70 800 9949

David ZetlandAssistant Professor

Topics: Commons, economics, entrepeneurship, environment, water, climate change

+31 (0)6 2890 9774

Brandon ZichaAssistant Professor

Topics: Institutional analysis of organizations, agenda setting, policy representation, political parties

+31 (0)70 800 9354

Dimiter ToshkovAssociate Professor

Topics: European Union politics, comparative public policy

+31 (0)70 800 9391

Sarah GiestAssistant Professor

Topics: comparative public policy, environmental policy and regulation, big data and policymaking and urban innovation

+31 (0)70 800 9490

Jaroslaw KantorowiczAssistant Professor

Topics: Fiscal policy, international organizations, constitutional change, judicial review, public policy evaluation

+31 (0)70 800 9500

Sinisa VukovicAssistant Professor

+31 (0)71 527 2727

Rob de WijkProfessor International Relations and Security

Topics: Conflict analysis, diplomacy, international relations, security

+31 (0)70 318 4848

Herman SchaperProfessor Peace, Justice and Security

Topics: Counterterrorism, diplomacy, international relations, terrorism

+31 (0)70 363 0105

Alexandre AfonsoAssistant Professor

Topics: Austerity, immigration policy, labour market reforms, public administration, welfare state

+31 (0)70 800 9923

Caroline ArchambaultAssistant Professor

Topics: Development, gender, human rights, youth Africa

+31 (0)70 800 9963

Madeleine HosliProfessor International Relations

Topics: European integration, international organisations, international political economy, international relations, public administration

+31 (0)70 800 9581

Maarja BeerkensAssistant Professor

Topics: Governance, higher education policy, international governance, markets in the public sector, policy instruments, public administration, regulation, science policy

+31 (0)70 800 9423


Leiden University College The Hague (LUC) offers excellent students an international English-taught Liberal Arts and Sciences bachelor’s programme on the theme of global challenges. Graduates of this programme regularly find positions at ministries, consultancy firms and NGOs, where they work to promote a better world, either in public view or behind the scenes. 

Anyone who is interested in approaching global challenges can also opt for a Public Administration programme. In terms of public administration, Leiden is one of the oldest, largest and most respected institutions in the Netherlands. The University offers a Dutch-language bachelor’s in Public Administration and a follow-on master’s focusing on governance of societal challenges.

Both programmes benefit from the stimulating environment of The Hague, an international city of peace and justice. Experiential experts from the city give guest lectures at the University and welcome students in their organisations as interns or researchers.

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