Interview with Renos Vakis
- Merle van den Akker
- Jul 6
- 9 min read
Behavioural Science is a rapidly expanding field and everyday new research is being developed in academia, tested and implemented by practitioners in financial organisations, development agencies, government ‘nudge’ units and more. This interview is part of a series interviewing prominent people in the field. And in today's interview the answers are provided by Renos Vakis.
Renos brings behavioral science to the forefront of policy design, shaping how governments address some of the world’s most pressing development challenges. As Head of the Mind, Behavior, and Development Unit (eMBeD) at the World Bank’s Development Impact Department (DIME), he leads an interdisciplinary team working across a broad range of policy areas to improve outcomes at scale. This includes human development—such as improving school performance, promoting healthier behaviors, and enhancing mental well-being and aspirations; government effectiveness and public institutions—by addressing service delivery bottlenecks, strengthening policy uptake, and increasing frontline accountability; and climate-related challenges—by supporting climate adaptation and shifting social norms around resource use. Through his leadership at the Institute for Economic Development (IED), Renos drives work on knowledge diffusion, impact analytics, and AI integration. This, along with his broader portfolio, focuses on scaling behavioral solutions, accelerating experimentation, and making knowledge more actionable, accessible, and widely used by policy and practitioner communities. He actively promotes the adoption of behavioral science through global advisory work, teaching, and speaking engagements with governments, development partners, and the wider behavioral science community. He holds a Ph.D. from the University of California, Berkeley—and brings not only academic and policy insights, but also his skills in magic and music, helping make the practice of development more engaging, creative, and impactful.
Who or what got you into behavioural science?
It wasn't an overnight shift, but early in my career, I worked on randomized trials and cash transfers in Nicaragua. We were helping women set up small enterprises, and as an economist, I initially approached it as a data-driven trial. But while engaging in fieldwork, I noticed something intriguing—women were not just receiving money and starting businesses. They were forming social networks, learning from each other, and developing motivation beyond financial incentives.
We found a way to measure how these social interactions were driving productivity and aspirations, doubling the impact of the cash transfer itself. That was my first realization of how psychology, social interactions, and mental models shape economic behaviour. I wasn’t thinking of it as "behavioural science" at the time, but it was fundamentally about how people think, interact, and make decisions.
At the World Bank, behavioural science wasn’t a well-defined function when we started. There were people applying behavioural ideas, but it was scattered and informal. A big turning point was the 2015 World Development Report, which focused on mind, society, and behaviour. It put behavioural science on the radar within the World Bank and created a natural entry point to ask, "What are we actually doing with these insights?"
From there, we followed a structured approach to building the team—ironically, much like we now advise governments to do when setting up their own behavioural units. We identified champions within the organisation, built early proof-of-concept projects, and demonstrated real impact. Initially, we were like a small startup within a massive bureaucracy—it wasn’t an easy process, but by consistently delivering results, we were able to institutionalise behavioural science at the World Bank. Over time, the team grew from an experiment into an established function, working across multiple sectors and countries.
What is the accomplishment you are proudest of as a behavioural scientist? And what would you still like to achieve?
One of my biggest achievements is co-founding and establishing the behavioural science team at the World Bank. Starting a new unit in such a large bureaucratic organisation was not easy—it required persistence, a growth mindset, and a lot of navigating institutional structures. We had to prove our value by demonstrating that behavioural insights could add to development policies and interventions.
Looking ahead, I see a huge opportunity to integrate behavioural science with technology to scale impact. We’ve had hundreds of experiences, many documented, many not, and I believe we can create public goods—tools, frameworks, and methodologies that governments and organisations can adopt at scale. AI and machine learning, in particular, offer exciting possibilities to enhance behavioural diagnostics and interventions.
How do you think behavioural science will develop (in the next 10 years)?
You know, we are at this age where every day, we’re getting a 10-times stronger tool in machine learning and algorithmic approaches. And I feel there’s this opportunity to leverage that, to do two things: first, as a diagnostic tool, because I feel now we have capabilities to extract insights in a much faster way about our biases, about behaviours that don’t conform to expected norms. This gives us a different kind of strength in designing interventions because we’re now able to do this large data analysis that we simply couldn’t do before.
Similarly, I think AI also opens way too many ideas in terms of creating practical tools that help people through interventions. So, I’m envisioning a world—whether for better or worse—where we all have AI assistants at the palm of our hands, helping us make decisions, nudging us toward better choices in real time. That raises big questions about adoption, about ethics, about how these things will evolve, but ultimately, it is a tool, and there are so many incredible applications we haven't even begun to explore.
And then there’s the bigger challenge of where behavioural science itself is going. I always felt that there was this unnecessary misconception that behavioural science is just about small effects, that it’s about tweaking little things rather than going deep. But I think we’ve done a lot to show that behavioural science is much broader—it's about shifting norms, changing mindsets, and thinking about behaviour at a systems level. The next phase is about embedding it deeply, not just as an external tool, but as something integrated into policy, economics, and technology. The more invisible it becomes as a standalone field, the more successful it will be.
What are the greatest challenges being faced by behavioural science, right now?
You're asking an optimist to be pessimistic.
I think some of the challenges are exactly the same challenges of any other discipline. At this point, at least from where I'm sitting, my main issue is there's only 24 hours in a day to do things. But I do feel there's this interesting moment happening where a lot of other disciplines are becoming more open to behavioural science, even if they don't always call it that. There are teams doing work that I would absolutely consider behavioural science, but they just don’t label it that way. That’s a good thing because it means the field is spreading, but it also creates challenges in terms of maintaining quality and rigour.
Scaling is always a challenge. We now have over 600 behavioural science teams in the public sector alone, and that's almost double what we had five years ago. That kind of rapid expansion is great, but it also means there’s huge variation in how behavioural science is applied—some teams are incredibly rigorous, while others are much more superficial. That creates risks, because if behavioural science is not applied well, people start to doubt its usefulness.
Another challenge is integration. Behavioural science works best when it's embedded in institutions, not treated as a one-off tool. But that takes time, persistence, and champions who really understand its value. I think the next step for the field is making sure it’s not just an external intervention but something fully woven into policy, economics, and technology. That’s how it will have the biggest impact.
With all your experience, what skills would you say are needed to be a behavioural scientist? Are there any recommendations you would make?
Curiosity is key—the best colleagues I’ve worked with are comfortable questioning the status quo and embracing uncertainty. In many ways, being a behavioural scientist means admitting you don’t know the answer upfront. Instead, you work with others to diagnose problems, test solutions, and learn from the data.
You also need analytical skills, particularly a solid understanding of statistics and data patterns. Behavioural science is about moving beyond the “average human” and understanding heterogeneity—how different people respond in different contexts. That requires the ability to work with data conceptually and statistically.
Beyond that, I’d encourage an interdisciplinary mindset. Don’t just stick to one field—pull insights from psychology, economics, neuroscience, history, and more. And finally, talk to people—networking is invaluable both for learning and for finding opportunities in the field.
What advice would you give to young behavioural scientists or those looking to progress into the field?
First, behavioural science is one of the best jobs you can have—you get to work on almost anything that involves human behaviour, which is basically everything. But to succeed, you need to embrace an interdisciplinary approach.
Study behavioural economics, but also take courses in psychology, neuroscience, or even history. Understanding behaviour from multiple angles makes you a better problem-solver. Develop strong analytical skills—statistics, data analysis, and even machine learning will give you an edge.
Also, engage with people. Talk to experts, attend events, and learn from those in different fields. A lot of opportunities come from conversations, not just job applications. And finally, be open-minded. The best behavioural scientists don’t just apply existing theories—they adapt, test, and create new ones.
What is your biggest frustration with the field as it stands?
If I had to pick one, it would be the overuse of the term "nudge." It sometimes diminishes the depth and seriousness of behavioural science, making it seem like it's just about small tweaks rather than fundamental insights into human behaviour. While the "nudge" approach helped bring behavioural science into the mainstream, it doesn’t fully capture the complexity of the field, especially when dealing with large-scale policy issues.
If you weren’t a behavioural scientist, what would you be doing?
I’ve always been passionate about development, but early on, I was at a crossroads. When I applied to university, I was interested in both economics and computer science. I actually applied to multiple universities for both subjects and got accepted in both fields.
The final decision was made based on a practical factor—my brother was studying in California, so I chose the closest campus where I had been accepted. And that happened to be for economics. Looking back, I sometimes wonder what would have happened if I had pursued computer science instead. Given that I was in California in the early ‘90s, right before the tech boom, I can probably guess—I’d likely be working in Silicon Valley, perhaps in AI or some other tech-driven field. Maybe I’d have become a tech entrepreneur—who knows? But I have no regrets. My path in development and behavioural science has been incredibly rewarding, and I wouldn’t change it for anything.
How do you apply behavioural science in your personal life?
I don’t think it’s possible to be a behavioural scientist and not apply it in your personal life—it just seeps into the way you think and make decisions. Lately, I’ve been particularly interested in healthy aging—both personally and professionally. It started as something I wanted to understand for my own health, but it’s now a growing focus in my work. I’ve been testing different behavioural strategies on myself—habit formation, goal setting, self-monitoring—to see what sticks and what doesn’t. Like most people, I’ve had more failures than successes, but the number of failures I do not wish to mention in this interview!
Healthy aging is one of the biggest public health challenges we’ll face globally. Right now, most health systems are focused on treatment rather than prevention. I believe behavioural science has a huge role to play in shifting that balance—helping people adopt better long-term habits and making structural changes to support healthier lifestyles.
So, in a way, my personal behavioural experiments are feeding back into my work—following my passion in a very practical way.
Who has really inspired you in behavioural science, and should I interview you next?I admire people who push us to think in new ways, who challenge assumptions and explore frontiers. I probably can’t say there’s one person who inspired me to do this or not, but I think some of the most interesting work is happening in places we don’t always look—people in development, in local contexts, tackling behavioural problems in ways that are deeply rooted in their environments.
If I were to advise you on who to interview next, I’d push you to find those voices—the behavioural scientists working in places where the challenges are unique, where innovation is happening out of necessity. There’s a lot of incredible work that isn’t always in the mainstream spotlight. The best insights often come from those dealing with behavioural problems in their own communities, with firsthand experience of how interventions play out in real life. That’s where the future of behavioural science is being shaped.
Thank you so much for taking the time to answer my questions Renos!
As I said before, this interview is part of a larger series which can also be found here on the blog. Make sure you don't miss any of those, nor any of the upcoming interviews!
Keep your eye on Money on the Mind!
