An interview with Carlo Ratti
In this conversation, architect and urban thinker Carlo Ratti reflects on how cities are changing – not so much in their physical structures, but in how we live, move, and connect within them. Drawing on his work with real-time data and urban planning, Ratti discusses the evolving "software" of cities, the role of feedback loops in both short- and long-term planning, and the importance of transparency and trust when it comes to data. He also shares his thoughts on the biggest challenges cities face in the years ahead, from climate adaptation to building more inclusive urban environments.
Carlo Ratti (CR): Cities have been evolving, both in software and hardware. The hardware hasn't changed that much. If you think of our cities, we are still living in places that were built hundreds or even thousands of years ago. We as humans and the fundamental things we need are always the same. We need horizontal floors, facades to protect us from the outside, and windows to look outside. So that is very permanent. But the software has been changing a lot. The software is the way we meet, mate, work, shop, and so on.
Looking at these different dimensions, what is success? I think the metrics are exactly the same today as they were in the past. When cities started 10,000 years ago, their success was to bring people together. I would say that today, as well, a successful city is a city where the community of citizens comes together in a cohesive way. A city where the sum is more than each of us individually.
When cities started 10,000 years ago, their success was to bring people together. I would say that today, as well, a successful city is a city where the community of citizens comes together in a cohesive way.
CR: Absolutely, I think it's about getting different types of frameworks. The amazing thing that we're getting with data is feedback loops, meaning that in real time, you can know something and respond to it. For instance, you know where the bus is in real time and decide to go and get it. If there's a delay with a train, you know how to find the closest bike or car share. These are quick feedback loops, but there are also slow ones at a city management level. For example, somebody will do a design, you'll share it with the citizens, they will provide feedback, it will go to the next iteration, and eventually it will be built.
So I think data is interesting because it allows us, for the first time, to get closer to the world of biology. To generate feedback loops as in nature. And to mix the micro and macro. In economics and also in urban science, these have always been seen as two different approaches. But now, data can blend them together. In short, data is the glue to merge both short and long term, fine-grained and large-scale.
Using data and feedback loops, citizens can get information in real time. Source: Adobe Stock
CR: I think there are many applications that have already been happening. In 2006, I presented at the Venice Biennale about how we are using data from networks in order to see the real-time city movements and flows. At the time, it was experimental. Now, it happens in our pockets every time we open a Google Map. Cities are using data as an input for planning with great success. It can tell us about flows, crowds, types of activities, and where they happen in the city. Then, governments can use this information to intervene and transform the city. The problem is that data today has ownership issues, and that's something I'm very concerned about. Some of this data is not even accessible for public use – it is on the servers of private companies and used in a non-transparent way.
There is only one principle that should apply to both private and public, which is transparency. It’s really about giving people the power to better manage and understand their data.
CR: There is only one principle that should apply to both private and public, which is transparency. Things such as the European General Data Protection Regulation (GDPR) go in the right direction. It’s really about giving people the power to better manage and understand their data. It inspired, among others, California’s privacy legislation. I think we should move increasingly in that direction - transparency in how data is collected and used, as well as agency for people to decide about their own data.
CR: Some key challenges are how cities can bring us together better, as we were saying before. How can we make cities that are more inclusive? Another important dimension is, of course, how we can face a more extreme climate. In order to face crises such as the floods in Valencia or the fires in Los Angeles, we need to move from mitigation to adaptation. Mitigation is still very important, but architecture now also has to adapt. Architecture can save us in the face of more adverse conditions.
I also want to add that in most of the world, the urban population is going down. So we don’t need to build more – we just need to make what we have better, safer, and more resilient.
An architect and engineer by training, Professor Carlo Ratti teaches at MIT and the Politecnico di Milano. He is the director of the Senseable City Lab and a founding partner of the architecture and innovation office CRA-Carlo Ratti Associati (Turin, New York City, and London). Carlo Ratti has been appointed as the Curator of the 19th International Architecture Exhibition at La Biennale di Venezia in 2025.
This article is based on an interview conducted by Laura Valdés Cano, with the invaluable support of Oscar Chamat-Nuñez, and editorial assistance of Caitlin Law and Juliette de Gouberville. The text has been edited for readability purposes.