Is Strategic Environmental Management, as a vision and approach, truly up to the challenge of the trends in our society? The Friday afternoon professional discussions at the office seemed valuable enough to Bas Liebeek and Jeroen Medema that they wanted to share them more often with a wider audience. That’s why they decided to launch a podcast in 2024. With two seasons of “Proef op de SOM” now under their belt, in each episode they delve into a topic related to the field of environmental management together with a guest.

The topics are drawn from the day-to-day work of WesselinkVanZijst and its guests and follow a set format. Each episode features a guest and focuses on an overarching theme. Themes range from the role of trust and AI to the increasing complexity of societal challenges or the integration of context-based working into organizations. Recurring segments include the Stefan Szepesi column and the guest’s reading, listening, or viewing recommendation.

Trial on the SOM Gets a Second Season: ‘We're Showing the Stubborn Reality of Environmental Management’

December 9, 2025 Amber Visch

• Podcasts & videos

Read more

The podcast now consists of two seasons, which have already been listened to more than a thousand times. In season 2, Bas and Jeroen will also go a step further: in addition to individual episodes, there will also be trios around themes that deserve more depth, and they will consciously seek out ‘abrasive’ topics that are further removed from their own expertise.

Trial on the SOM Season 1

Listen to the most recent episodes below, or follow Proef op de SOM on Spotify. Jeroen and Bas love to connect with listeners. So if you have a question, topic, or feedback you'd like to share? Bas and Jeroen would love to hear it! You can email suggestions to info@wesselinkvanzijst.nl.

Episode 1: Johanneke de Lint

Johanneke de Lint can rightly call herself an experienced environmental professional. She has been active in the field for nearly 25 years. Johanneke studied Law in Amsterdam and specialized in Corporate Governance and Corporate Social Responsibility. In her first job, she was captivated by the power of good stakeholder dialogue. Throughout her career, she has further developed this as a mutual gains advisor and strategic environmental manager. In this episode, we discuss the necessity of investing in good relationships. And that this takes time and attention, also from the initiator.

Episode 2: Marc Wesselink

Marc has been working as a consultant since the late eighties. He is the author of the Handbook of Strategic Environmental Management and the Handbook Strategic Environmental Management 2.0 the founder of SOM. Marc has together with Hans van Zijst In 2010, the company WesselinkVanZijst BV was founded. His work for the project Maasvlakte 2 delivered a unique combination of practice and theory, resulting in the birth of the SOM methodology. For this, Marc won the ROA Advisory Prize (Council of Organization Consultants) for the best Dutch Advisory Assignment. Since then, the Strategic Environmental Management method has been increasingly applied in various assignments in the Netherlands and abroad. We discuss with Marc the 4 principles of genuine connection, including by reflecting on the A.A.R.C. principles.

Episode 3: Janneke de Jong

Janneke de Jong is Director of Participation at the Ministry of Infrastructure and Water Management and Secretary-General of the Consultation Body for the Physical Living Environment (OFL). After studying Political Science at the University of Amsterdam, Janneke started as a trainee at the then Ministry of Housing, Spatial Planning and the Environment (VROM). She then worked at the Ministry of Finance, returned to VROM/IenW, where she held various positions, including project manager for environmental management for the Environmental Quality Act. In 2014, Janneke completed the SOM leadership program, where she was inspired by the MGA and SOM philosophy. With Janneke, we discuss how to make room within your own organization for the interests of others. And why you cannot make good policy without truly understanding what is happening in society.

Episode 4: Zita van Aggelen

Zita van Aggelen She is an experienced all-rounder in our field. Her experience ranges from organizational change, executive advisory, team management to project/program management. And of course, as an environmental manager and SOM expert. Her passion lies in helping organizations involve their environment in the (primary) process and vice versa. Zita always works from a combination of technology and people. Based on her background as a structural engineer, her work at network operators (cables and pipelines) and the energy transition, she has a clear view of what is technically needed and combines that with a people-oriented approach.

This will serve her well in her work for various cooperatives in the energy sector. We speak with Zita about the role of cooperatives and why they are so successful with the empowerment participation level. A level that we rarely encounter in the field, but perhaps unfairly so? And what does empowerment mean in practice? For both the cooperative, and also for, for example, the municipality?

Episode 5: Joost Stoffers

Joost specializes in the subject of resident participation and works as a participation advisor for the municipality of Lelystad. With a background in both the hard technical side (he once studied MBO electrical engineering and business administration) and the softer communication side (specializing in government communication), he can handle himself well in various situations. This is necessary, given the wide range of topics he encounters and the large number of resident evenings he attends, where the field of participants also varies greatly in terms of background, interests, expertise, knowledge level, etc.

He started his career at the municipality of Amsterdam, where he also graduated. He worked on various projects in every district, often related to participation, even if only as part of a communication plan. Subsequently, he moved to the municipality of Lelystad as a communication advisor. He prefers to focus on helping to properly organize participation processes, as that turns out to be quite complicated.

Episode 6: Hans van Zijst

Memoranda of Understanding, BOKs, SOKs, ROKs—these agreements are everywhere these days, in all sorts of different terms. But what is a (good) agreement? And what’s the difference between the various types of agreements? What should you include in them? This new episode of “Proef op de SOM” focuses on (administrative) agreements. Featuring none other than a pioneer in the field—Hans van Zijst.

Hans van Zijst can rightfully be called one of the icons in our field. He has had a long and rich career: as a graduate lawyer, he worked on national environmental policy, represented the Netherlands as an environmental diplomat in the United States and Canada, conducted international environmental negotiations for the Netherlands, and was responsible for global environmental policy at the former Ministry of Housing, Spatial Planning, and the Environment. As a consultant, he successively worked at the international environmental consultancy ERM and owned his own consultancy firm.

In 2011, together with Marc Wesselink the consultancy firm WesselinkVanZijst. He was thus at the forefront of the current field of environmental management and has also contributed significantly to the establishment and professionalization of this field over the past 20 years. He was involved in, among other things, the realization of Maasvlakte 2, the Route Decision A4 Delft-Schiedam, the planning of the 380 kV high-voltage line Wateringen–Beverwijk, the route exploration for the Blankenburg Tunnel, and the development of Zuidas Project in Amsterdam South until 2024 at the third city bridge in Rotterdam.

Episode 7: Onno van Eijk

A good preparation is half the... Ho, stop!

According to our podcast guest, good preparation is truly more than half the battle. “To go far, you have to start slow.”

Onno van Eijk is a founding member of MGA. After 6 years as a project leader at the Netherlands Institute for Spatial Planning and Housing, he has now been working for the Province of South Holland for over 15 years. He is active as a strategic environment manager, project leader, trainer, advisor, and moderator/facilitator. In 2021, Onno won the Frans Evers Award for Mutual Gains. He regularly sees in practice the benefits of good preparation. Or, put another way: the price we collectively pay in the event of insufficient preparation. We talk about the hurdles that sometimes have to be overcome, the effort involved, and practical tools that can help us with this.

Episode 8: Margot Kwee

Diversity, inclusion, equality. Each of these is something that keeps us, as a country, or perhaps even the world, very occupied. Daily, we read about them in the news and on social media, and we experience them in practice. But what are we actually talking about when it comes to diversity, inclusion, and equality? What does it mean when you want to work on these? Can you also apply these concepts to the work of an environmental manager? And finally, the exciting question: how do we think we're doing ourselves?

Once again, we're putting the SOM to the test, but this time with Margot Kwee. Margot originally has a business background, having studied International Business Administration and International Management at Erasmus University Rotterdam. Yet she decided to focus primarily on the public sector. For the past 5 years, she worked for drinking water company Dunea as a strategic stakeholder manager. In June 2025, she moved to the OER (Generation Energy on State Land) program of Rijkswaterstaat. In addition, she is a general board member at the Schieland and Krimpenerwaard District Water Control Board for Water Natuurlijk.

In all these functions, she regularly addresses the themes of diversity, inclusion, and equality. She is also the founder of the diversity, inclusion, and equality coalition in the water sector, and she provides training for more diversity and inclusion, among other things. Both within the water sector and in other societal sectors. Together, we will discuss these important concepts and what they can mean for the profession of the environmental manager.

Episode 9: Marcel Hoogsteder

Data. Who doesn't get excited about that? For most stakeholder engagement managers, data isn't the sexiest concept. At the same time, there are very few roles where as much data is collected as in stakeholder and environmental management. The only question is: how much of that data is actually utilized? You can view data simply as ones and zeros. As binary code. But in our work, this is about much more! For example, information from emails, conversations, or meetings. Information about interests, positions, emotions, BATNAs, solution directions, history, urgency, etc. And yet we see that too little information is processed properly. And that is a shame, argues our guest Marcel Hoogsteder.

Marcel has been working in environmental management for about 15 years, primarily on large infrastructure projects, from the initial planning phase through to completion. He has worked for companies such as Ballast Nedam, Rijkswaterstaat, and the Municipality of The Hague. Throughout these projects, he always noticed one thing: while the work of environmental managers is becoming increasingly complex, we are lagging behind in how we handle data and information. Everything is in people's heads, emails, and scattered notes – but there's no overview or structure anywhere. 

That insight ultimately motivated him to found the company Dialog with a few partners. Not as an IT project, but as a tool for environmental professionals. So that they spend less time searching and reporting, and more time on what truly matters: stakeholders who feel heard and involved. Together we discuss the role of data in environmental management. What it is, how it is currently used, and what it could be.

Episode 10: Eefje Rolsma

Stop the arrogance in environmental communication!

In the latest episode of Taste on the SOM, we have Eefje Rolsma Guest. Eefje studied Humanities at Utrecht University and Public Affairs in Leiden. Her preference for complex social challenges grew during her first real communication job: getting her boots in the mud at the former Rural Areas Department of the Dutch Ministry of Agriculture, Nature and Food Quality. After that, she served the King's Commissioner in North Brabant as a spokesperson on behalf of 14 political parties. There, her political-administrative antenna was further developed. Eefje has been with Connect Communicatie since 2018, where she has been Managing Partner since 2021.

Connect Communication is a Flemish-Dutch communication agency with 65 critical communication professionals focused on Environmental Communication. They publish the "Vakblad voor Omgevingscommunicatie" (Journal for Environmental Communication)! Connect aims to connect people and their environment. This means looking beyond the boundaries of the communication profession.

Eefje takes this "peeking over the fence" to heart herself. We saw her as a participant in various Strategic Environmental Management Training. With her, we discuss, among other things, the differences and similarities between SOM and COM. We delve deeper into verbal and non-verbal communication and uncover a concern of Eefje's: “Communication is more than packaging your message, more than sending out what the organization needs.” Eefje suggests that organizations should focus less on their own tasks and more on engaging with the outside world.

Episode 11: Fenneke van der Vegte

In the latest episode of Proef op de SOM, we speak with our colleague Fenneke van der Vegte Over society and politics. Or, the arena of dialogue and the political arena. How do these arenas relate to each other? Are we mainly hindered by them? Or can they strengthen each other? 

Fenneke takes us through the research that she and our colleagues Thijs Kraassenberg carried out within the Ministry of Economic Affairs and Climate Policy (EZK), the Ministry of Health, Welfare and Sport (VWS), and the Ministry of Infrastructure and Water Management (IenW). In it, they investigated the question: how do we incorporate the political arena into the ministry's environmental processes? Is working solely according to the SOM methodology sufficient for this? Or is more needed?

Fenneke herself is also politically engaged. She has been working in the public sector for some time, including as a policy advisor in Zeist and as a strategic advisor for the municipality of Amersfoort. She served as a council member and later became an alderman for the municipality of Leusden. And for some time now, she has been a colleague at WesselinkVanZijst! Fenneke will guide us through the research findings using a number of lessons.

Episode 12: Gold on the Marathon

After twelve months and as many episodes, we are marking an important milestone! This episode not only concludes the first year but also serves as the starting point for a new season. We ended season 1 in style: with gold at the Marathon.

Special location

This twelfth episode was recorded during the annual Dating marathon van WesselinkVanZijst. At this two-day event, held in the middle of nature and away from the daily hustle and bustle, our team reflects on the development of our field and we work together on new ideas for knowledge development. It was the ideal place to put colleagues to the test, ask some questions, and look ahead together.

Taste of the SOM Season 2

Episode 13: Engaging large groups of people with Participatory Value Evaluation (PVE) – with Shannon Spruit

Most environmental professionals are familiar with the dilemma: you have a task that affects a large group of people. This often involves local residents (or ‘citizens, inhabitants, or residents’). But how do you effectively involve such a large, heterogeneous group of people with diverse opinions and interests in your project? We spoke Shannon Spruit about this. Shannon is, together with Niek Mouter, co-founder of the company Populytics and they work with Participatory Value Evaluation (PVE).

Populytics was the first to implement this method for citizen participation. Its application of PWE for energy policy in the municipality of Sudwest-Fryslân was nominated for the Galjaard Prize for communication. This success led to the establishment of the company Populytics in 2020, and the company has since rapidly grown into a 20-person organization. Since then, over 300,000 people, across more than 120 Dutch government bodies, have been advised on complex policy issues through Populytics' PWE consultations. They conducted them for, among others, the National Citizen's Climate Assembly, where over 35,000 people contributed to climate policy in the Netherlands.

Together, we will discuss the role of this method in environmental management. What it is, how it is applied, what challenges still exist, but also what opportunities are seen. 

Episode 14: Experimenting with AI – with Marc Wesselink and ‘Chat’

There's no escaping it in recent years: Artificial Intelligence, or AI. And although the concept and certain applications have naturally existed for a longer time, AI seems to have taken a significant leap forward with the arrival of various new language models, such as ChatGPT and Co-Pilot. Almost daily, we are confronted with new possibilities and applications across numerous fields. 

AI also offers the necessary help for the work of environmental professionals. But we see around us that AI is only being used sparingly. And if we look honestly at ourselves, we also still use it relatively little. That's why for this episode, we've undertaken the experiment to see what an AI agent can do for our daily work. And who better to have such a conversation with than an AI agent itself. In person! Or, well, alive... in any case, lifelike.

We're taking the Proof of the SOM and going, together with the personal AI bot of Marc Wesselink and himself, discussing the potential applications of AI. And trying that out right away in this experimental episode of Proef op de SOM.

Episode 15: Coloring Outside the Lines – with Sabine Kern

Environmental professionals work in a world full of frameworks. Legislation, policy, procedures, administrative agreements. Those frameworks surround every project as a given. But what if those frameworks are not the solution, but part of the problem? And what if true craftsmanship lies in finding the space *outside* those frameworks? Without ignoring the rules?

In this episode, we're talking Sabine Kern, Director of Development, Strategy and Transition at Limburg Water Board. Sabine built her career at Rijkswaterstaat, the Province of Limburg, and the Flood Protection Program. Each of these environments is characterized by high pressure, complex interests, and rigid frameworks. There, she learned integrative negotiation. She worked in people's backyards on flood defenses. She held discussions with village councils about public transport concessions. And she drew a conclusion: whoever waits for the solution to fit within the frameworks often waits too long. Or forces a painful outcome that no one wants.

Sabine's plea is clear and challenging at the same time: civil servants and professionals must show courage. Seek out creative space. Broaden the appealing prospect instead of shrinking it. Not as an act of disobedience, but as professional responsibility. We discuss how to do that: involve managers early, explain the ugly alternative, make complexity understandable, bring in the right expertise, and don't shy away from the less pleasant consequences of choices.

Episode 16: Tightrope Walking at the Ministry of Defense – with Jos van der Leij

It could hardly have escaped your notice in recent years: increasing threats in the world require our armed forces and other Western democracies to rapidly scale up their military forces and quickly expand their capabilities. Therefore, heavy investments are being and will be made in Defense. More personnel are being added, more equipment, more training must take place, and therefore expansion opportunities are being sought at a rapid pace everywhere in the Netherlands. The National Programme for Space for Defense (NPRD), definitively adopted in December 2025, maps out the necessary spatial expansion needs of Defense.

The NPRD also demonstrates that the defense organization must not only intensify its personnel, but also that environmental management has received a major boost. From an organization that primarily returned space to the surrounding area, to an organization that must grow significantly within a few years and also requires the necessary space to do so. While that space is scarce everywhere.

That requires a complex balancing act, professional tightrope walking. On the one hand, to make room for the interests of Defence in the outside world, where Defence is a relatively ’new’ claimant to space. On the other hand, to make room for the interests of the outside world within an organization that is getting used to thinking about that. And although the willingness is there to do it well and carefully, too much (too much?) needs to be done in a short amount of time. How do you deal with that then?

We are taking with Colonel Jos van der Leij, Head of the Living Environment Department and Program Director of the National Programme Space for Defence, the Trial of the SOM .

Episode 17: Building trust, you have to do that yourself with Theo Kion

You do not build trust with methods, templates, or playbooks. You build it with yourself, with genuine interest, the courage to be present, and the willingness to change direction when you truly listen. That is the core of what Theo Kion has been doing his entire career. And it has taken him far.

Theo started literally on the streets of Rotterdam as a military policeman and police officer. From neighborhood team manager in Oude Westen, he worked his way up to area manager and strategic advisor for the municipality of Rotterdam, subsequently developing into an environment manager for multiple projects, including the complex area developments of Feyenoord City and Stadionpark. Politically charged, with an impact on many people and often in the spotlight.

And then a motion comes from the Rotterdam municipal council that points to his participation approach as an example of how it should be done. Not because of the complexity, but thanks to the way he (and his colleagues) handled it.

In this episode, we talk with Theo about what participation means in practice when you take it seriously. About the capabilities, competencies, and character a good stakeholder engagement manager needs. About how to deal with resistance and why he actually considers action groups the best thing that can happen to a stakeholder engagement manager. And about his advice to a field that he is leaving behind on the eve of his retirement.

Theo is no theoretician. He knows SOM from a book, but even more from the streets, from kitchen table conversations, resident meetings, and difficult negotiations. His insights are therefore as practical as they are sharp.

Episode 18: Daring to Engage in Dialogue with Amber Bosse

How do you have a good conversation when opinions are diametrically opposed? And what role can dialogue play in complex social issues?

In this episode, we talk with Amber Bosse, mediator and process facilitator at Public Mediation. Every day, she guides governments, organizations, and residents in situations where interests clash, tensions rise, and cooperation is anything but a given.

Together we explore what dialogue actually is and, perhaps more importantly, what it is not. We discuss polarization, participation, and democratic resilience, as well as the practical side of decision-making. When is it wise to first make room for conversation? And how do you prevent endless talking from coming at the expense of progress? Amber shows that a good process does not begin with agreement on the substance, but with agreements on how you treat one another. Because when the relationship comes before the agenda, room is created to have difficult conversations as well.

An episode for anyone working on social challenges, participation, stakeholder engagement, or collaboration in complex environments who is curious about how dialogue can contribute to better decisions and stronger relationships.

Don't want to miss an episode? Then subscribe via Spotify. New episodes will then automatically appear in your feed.