Urban Models: C40's Director of Urban Planning and Design Hélène Chartier on A New Paradigm for Cities
By Julia Gamolina
Hélène Chartier is the Director of Urban Planning and Design at C40. She supports cities to accelerate climate-responsive urban planning policies and resilient design. Her team leads world-leading initiatives such as C40 Land Use Planning Network, Green and Thriving Neighbourhoods Forum and Reinventing Cities —a series of competitions delivering zero-carbon urban regeneration projects around the world.
Hélène previously served as an advisor to the Mayor of Paris and has lived in Paris, London, and New York. In her interview with Julia Gamolina, Hélène talks about cities as drivers of transformation, the urban projects that she’s had a hand in, and the ambitious goals of new urban planning models. She advises those just starting their careers to stay curious and flexible.
JG: I could not think of a more urgent issue than addressing the climate crisis, especially in cities around the world. What do you have planned with C40 Cities for 2025, and what's the most important thing all of us should know about and pay attention to as we start the year?
HC: Cities play a critical role in addressing the climate crisis. They’re responsible for most emissions and are home to populations most vulnerable to climate change. But cities also have progressive leadership and the operational capacity to drive transformation. At C40 Cities, by 2025, we aim to scale up the implementation of climate action plans across our global network, advancing the shift to net-zero and strengthening climate resilience, particularly in vulnerable communities. Climate equity is central to this—solutions must not only reduce emissions but also address the disproportionate impacts on marginalized communities.
Integrating climate goals into master plans and urban planning policies is especially critical. By the middle of the century, urban areas could triple in size, with significant consequences for natural ecosystems, greenhouse gas emissions, and vulnerability to climate-related risks such as flooding, heat waves, and water scarcity. Good urban planners are therefore the best climate activists: their decisions today will define cities’ capacities to meet climate goals and enhance quality of life for all residents, now and long into the future.
C40’s Climate Action Guide for Urban Planners. Courtesy C40.
How did your interest in cities initially develop?
I grew up in the suburbs of Paris, about twenty kilometers from the city center, in the "Ville Nouvelle" of Marne-la-Vallée. This area was a typical example of the dormitory-style urban development promoted by the French government in the 1970s and 80s. These new towns were characterized by single-family zoning, which consumed vast amounts of natural and agricultural land. They lacked essential amenities and services, and were primarily connected to urban cores by large transport networks that were mainly designed for car use. I watched my parents spend so much of their time commuting in traffic.
When my father became the mayor of our small town, he became deeply involved in the community's development. He was one of the first mayors in our region to challenge this urban model. Rather than continuing the trend of sprawling, car-dependent suburbs, he advocated for infill development, multi-family housing, and more affordable housing options. He also championed the creation of essential services and cultural amenities to bring life to our small town. Moreover, he fought to protect the surrounding natural landscapes, helping people understand their value in maintaining a healthy environment. Looking back, I realize how pioneering his vision was—and how profoundly it influenced my own academic and professional choices.
“Good urban planners are therefore the best climate activists: their decisions today will define cities’ capacities to meet climate goals and enhance quality of life for all residents, now and long into the future.”
You studied civil engineering and the environment. What were you hoping to do in the world?
I didn’t really know what I wanted to do, but I knew that I had a scientific mindset, and eventually civil engineering felt like the right fit. Over time, I found myself increasingly drawn to environmental issues, driven by a desire to understand how we could build more sustainable, resilient, and equitable communities. Now, twenty-five years after I began my studies, we are more aware than ever of the detrimental impacts of such urban models on climate change and biodiversity loss.
You worked at Arup, then in the Architecture and Construction Department of the City of Paris, and then for Apur. What do you take away from your experiences there that you still draw on today?
At Arup, in London, I developed a deep understanding of how integrated technical solutions—whether in infrastructure, building design, or energy systems—can address complex challenges. What I learned there was the importance of interdisciplinary collaboration and how essential it is to consider all aspects of a problem—environmental, social, and economic—in order to find holistic solutions.
During my time in the Architecture and Construction Department of the City of Paris, I was responsible for designing and overseeing the construction and renovation of public buildings in the 18th arrondissement. This was also my first managerial role, where I not only led a small team but also coordinated the efforts of a larger group of workers who were responsible for carrying out repairs in kindergartens, schools, cultural institutions, and other public buildings throughout the district. It was an amazing human experience and I learned a great deal about architecture, construction techniques, and materials.
Finally, at the Agence Parisienne d'Urbanisme (Apur) I gained firsthand experience in how urban policy and strategy can shape the development and regeneration of entire neighborhoods, both in Paris and the broader Greater Paris region. At that time, the metropolitan area had no coordinated governance or shared vision, which made the work even more challenging but also more rewarding. Not only did I learn the ropes of urban planning but it was also through this work experience that started my political engagement, first working with the team of Bertrand Delanoë, and later with Anne Hidalgo—the former and current mayors of Paris.
Courtesy of C40.
Yes, you were then an advisor to the Mayors of Paris! Tell me about what you learned.
I was deeply impressed with Bertrand Delanoé’s and Anne Hidalgo’s political leadership. Supporting them in overcoming political challenges and securing buy-in from Parisians to implement their projects was one of the most formative experiences of my career.
Anne Hidalgo, in particular, had a clear vision for the future of Paris. During my time with her, we focused on three main objectives: accelerating the ecological transition of Paris, implementing ambitious housing policies to ensure that people from all social backgrounds could continue to live in Paris, and building the metropolitan future of Paris, connecting the city with its surrounding suburbs. Key initiatives include transforming the city’s fringe areas to eliminate the physical and social barriers, and launching concrete projects like the Metropolitan Low Emissions Zone. Additionally, initiatives like the "Reinventer Paris" call for projects, coupled with the development of the new circular metro line, Grand Paris Express, have spurred urban regeneration across the metropolitan region. These efforts, together with the beginning of joint governance and budgeting for the wider metropolis, mark crucial steps toward realizing the city’s metropolitan future.
How did you come to C40 Cities? And where are you in your career today with this role?
After the passing of my father, which was a difficult time for me, my partner received an exciting professional opportunity in New York. It was a big step for our family and, in a way, also an opportunity for me to move forward. Coincidentally, around the same time, Anne Hidalgo was about to become Chair of C40. At that point, I didn't know much about this incredible organization. But the Mayor suggested I meet Mark Watts, C40's Executive Director, to explore potential projects under Anne’s leadership. That conversation led me to join C40, where I helped launch Reinventing Cities.
I now lead a team of brilliant people who, through the C40 Land Use Planning Network, are helping cities update their masterplans and integrate climate objectives into their urban planning policies. We also run the Green & Thriving Neighborhoods program, which aims to involve over forty cities in turning the fifteen-minute city concept into reality and developing neighborhood-scale pilot interventions. And, of course, we continue to run Reinventing Cities and its sister initiative, Youth Reinventing Cities, which has already empowered more than 13,000 students and academics to share their innovative ideas and climate solutions with mayors.
“Persistence is critical . . . I’ve also learned to build resilience in my teams and focus on the bigger picture. The road to meaningful climate action is not linear, but each step forward matters.”
Looking back at it all, what have been the biggest challenges? How did you both manage through perceived disappointments or setbacks?
The biggest challenges have often been the times when the scale of the problem has felt overwhelming. Climate change is a multi-dimensional and highly political issue, and sometimes it feels like progress is slow, especially when addressing it through cross-sectoral lenses like urban planning. Additionally, the lack of financial resources to support cities is a major hurdle. While many cities and mayors understand what needs to be done, they often lack the funds to implement effective actions.
One of the key ways I’ve managed through setbacks is by focusing on incremental progress and recognizing that real change takes time. Persistence is critical. Even small victories—whether it's getting a city to adopt a bioclimatic master plan or seeing local communities embrace sustainable practices—are important milestones. I’ve also learned to build resilience in my teams and focus on the bigger picture. The road to meaningful climate action is not linear, but each step forward matters.
Who are you admiring now and why?
Jane Jacobs is someone I deeply admire, especially for her pioneering approach to urban planning, which continues to influence how we think about cities today. Jacobs was truly ahead of her time in recognizing the importance of creating cities that prioritize people, not just cars or large-scale infrastructure. In many ways, Jacobs was the first to develop the core ideas behind what we now call the fifteen-minute city. Long before it became a popular concept, she championed the idea that cities should be compact and walkable, with essential services and amenities accessible to residents without needing to rely on cars, and with cultural life and public spaces that foster social interaction and active communities.
I also admire her for challenging the conventional wisdom of top-down planning and championing the role of community in shaping urban environments. Her emphasis on human-scale design, local engagement, and the organic evolution of neighborhoods has had a lasting impact on modern urban planning.
A plan for Milan, as part of C40’s Reinventing Cities project. Courtesy of C40.
What is the impact you’d like to have on the world? What is your core mission? And what does success in that look like to you?
I would like to contribute to support local and national governments changing the mainstream urban planning model. It’s now clear that the current paradigm is not only unsustainable but also a major driver of climate vulnerability. The statistics are clear: today urban areas are expanding 50% faster than population growth. Urban growth in flood-prone areas is outpacing development in low-risk zones. This problem is even more acute in the Global South where 90% of the urban expansion happens in or near extreme flood-prone areas. And most cities continue to expand on greenfield sites which increases their exposure to heat and flood risks.
Success, for me, would be to see a global shift toward climate-responsive urban planning, with widespread adoption of key principles like shifting from sprawling, low-density development to more compact urban areas that prioritize infill development; moving away from rigid zoning laws to create mixed-use neighborhoods that integrate residential, commercial, and recreational spaces, reducing the need for long commutes; replacing car-centric designs with public spaces that prioritize people and nature; and transitioning from top-down, one-size-fits-all planning to community-driven approaches where local residents actively participate in shaping their cities, ensuring that their needs and aspirations are met.
This would make a huge difference in the fight against climate change. According to the IPCC climate experts, a more sustainable urban planning model could reduce greenhouse gas emissions by 25% by 2050 compared to business-as-usual.
Finally, what advice do you have for those starting their career? Would your advice be any different for women?
My advice to anyone starting their career is to stay curious and flexible with your career path—sometimes the best opportunities come from the most unexpected places. Coming from an engineering background, I never imagined I’d end up working in politics or urban planning.
And for women, I would say: don’t undervalue yourself. A lack of confidence can be a real barrier to progress, so don’t let imposter syndrome hold you back. Be confident in your abilities.
This interview has been edited and condensed for clarity.