Amsterdam, 17 February 2026. Today marks the publication of The Happiness Code: the four contexts in which you can crack the code for happiness (without having to fix yourself), the new book by Astrid Groenewegen, co-founder of SUE Behavioural Design. The book offers a radically different take on happiness: not something you find inside yourself, but something you can design in the world around you.

Designing happiness in four contexts

The Happiness Code breaks with the dominant idea that happiness is an individual, internal project. Astrid Groenewegen shows that happiness emerges from the interaction between people and their environment, and that you can shape that environment. The book covers four contexts in which happiness can be designed:

  1. Personal happiness – How to redesign the choices and habits in your daily life so they contribute to greater wellbeing, without having to fix yourself.
  2. Happy relationships and teams – How the dynamics between people determine happiness at work and in personal relationships, and how you can influence those dynamics positively.
  3. Happy organisations – How organisations can design employee happiness by applying behavioural insights to culture, processes and leadership.
  4. Happy cities – How public spaces, policy and urban design can increase the collective wellbeing of residents.

Happiness is not a property of a person. It is a property of a situation. And situations can be designed.

With this approach, Astrid makes behavioural science practically applicable for anyone who wants to increase happiness, from individuals to HR directors, from team leaders to policymakers. Central to this is the theme of employee happiness, where SUE helps organisations design this structurally.

New programme: designing employee happiness

Alongside the publication of The Happiness Code, SUE Behavioural Design is launching a full programme around designing employee happiness. The programme translates the insights from the book into concrete tools and methods for organisations that want to structurally improve the wellbeing and engagement of their people.

The programme includes:

Astrid Groenewegen as a keynote speaker

With The Happiness Code, Astrid adds a new theme to her keynote repertoire. Alongside her existing talks on Behavioural Design and the art of behaviour change, she now also offers keynotes on happiness and wellbeing. Topics Astrid speaks on:

Astrid speaks in both Dutch and English, for groups of 50 to 5,000 people. She has previously spoken at events including Emerce eDay, NIMA, the University of Amsterdam and dozens of corporate events.

Webinars and community

For alumni of the SUE Behavioural Design Academy, SUE is organising a series of webinars around The Happiness Code in the coming months. During these sessions, Astrid translates the core insights from the book into the specific context of participants, whether that is HR, communication, leadership or policy.

Dates and registrations for the webinars will be announced shortly via the online academy and the weekly newsletter.

Further reading

Want to apply the ideas from The Happiness Code right away? Read our in-depth articles:

About the book

The Happiness Code: the four contexts in which you can crack the code for happiness (without having to fix yourself) is written by Astrid Groenewegen and published by Boom. The Dutch-language book is available at all bookshops and online via Managementboek.nl and Bol.com.

About SUE Behavioural Design

SUE Behavioural Design is Europe's leading Behavioural Design agency and training institute. From Amsterdam, SUE helps organisations and professionals understand and change human behaviour. With more than 10,000 trained professionals in 45+ countries, an average rating of 9.7/10, and a client portfolio that includes Rabobank, KPN, Heineken and the Dutch national government, SUE is the authority in Behavioural Design.

Press note

For press enquiries, review copies or to book Astrid as a keynote speaker: