Arthur Perez is a French urban designer, who relocated to San Francisco. We met him during The Night of Ideas 2023, where he took part in a panel with Mathilde Billet – resident architect of the Villa Albertine – “Make More Doughnuts! Let’s Make sustainable cities!”
With his career on two continents, Arthur explains the profession’s specificities between France and the United States. We also wanted to know more about his current projects in San Francisco, such as Downtown revitalization or the waterfront resilience.
Hello Arthur. In order to clarify, can you explain the difference between “planner”, “urban designer” and “urban planner”?
In the US, the planner is responsible for developing urban strategies and regulatory aspects of urban planning, and the designer for its design. In Europe, the town planner wears both hats and exercises a very interventionist mission: he combines strategic and design roles. It is a “top to bottom” system.
In the US, the planner has a more regulatory function of the city: It determines the conditions under which the city will be able to develop, etc. The designer will translate a strategic vision into a concrete plan on the territory – size the spaces – qualify the uses, etc., with the promoters, the citizens, the elected officials, and in the workshop to design the concepts of what he previously had analyzed. The system here is “bottom-up”.
How is an urban project carried out?
Initially, there is often a promoter who has bought land or buildings and wants to transform them. Its brand image will resonate with the rest of the city, so he works in cooperation with the citizens of the neighborhood for the public space to benefit everyone; part of the construction comes back to them and their activities. The idea is to reweave the urban landscape to make it work better and in a more user-friendly way.
For example, we worked on the 5M Project in San Francisco, around Mission and 7th Street, where there was a large Filipino community. The promoter has delimited certain spaces of his office/housing project, which are private but accessible to the public (they are called POPAs: Privately Owned Publicly Accessible), and has made sure to save a place for the community by creating public spaces, the preservation of their commercial activities and the creation of premises for neighborhood associations. In exchange for these “public benefits”, the project was able to benefit from more constructability: everyone wins.
What is the method used?
At SITELAB, we consider that each territory can find its own method. But in general, we try to determine the history of the place, in order to set it in its right context. We consult

Illustration courtesy of ©SITELAB urban studio
citizens about their wishes, their needs… and we try to plan for a prospective vision of the place, sometimes up to 100 years ahead. It is a collaborative work: the promoters finance the operations, sometimes with the help of the public authorities, or even some citizen fundraising.
The philosophy?
“Shaping cities from the ground up” which basically means that all the ingredients already laid down (inhabitants, history, typology…) will be taken into account rather than parachuting into a new project created without this context.
What was your professional background?
I am originally an architect but after several years of practice, I found that the architectural profession was too focused on the act of building. Building is not necessarily the most adequate answer. I, therefore, pursued urban planning studies and then learned to develop this new work first in Paris and then in San Francisco, at SITELAB. I also teach at Ponts et Chaussées.
What are the current plans to revitalize San Francisco?
First Downtown suffers from a perception problem, and that really has an impact on its revitalization. There is an urgent need to create more inclusive environments for all and to create access and opportunities for visitors and businesses to thrive in a post-COVID landscape. Then there is the embarrassing problem of the lack of housing as well as that of empty offices. But converting them will not be enough: a real project is needed to revitalize Downtown, with parks, shops, public spaces, mobility, and give citizens the desire to move there. All of these are gateways to thinking about this revitalization, and we, at SITELAB, enter the subject through public spaces.
The city, in concert with “non-profit organizations” is getting down to it and we are working with them on small projects to rehabilitate Downtown alleys, making them attractive, the time of a walk, an event, and creating the desire to rediscover a neighborhood.

Image courtesy of © SITELAB urban Studio
Another example: for two years SF Downtown Partnership has been presenting the “Let’s glow” project where images and videos are projected on the neighborhood walls during the end-of-year celebrations. Last winter our participation was adding culinary events, furniture, etc., to make the space convivial and thus change its perception. We also transform certain streets into pedestrian zone and create festive events, exhibitions, etc.
Then there is climate change, which will inevitably reshape the appearance of cities. In San Francisco, a large part of the waterfront is already in danger of collapsing, in the event of an earthquake.
We are working on this today in the office, by drawing up strategic plans over 100 years: the entire shoreline will be adapted to be resilient in the long term to sea-level-rise and seismic vulnerabilities, but always with this idea of constant work with the residents, and the diverse public and economic actors.
The city must not lose its relationship to the bay with a wall that protects it from flooding. San Francisco is a coastal city, which derives much of its beauty from it, and intends to remain so. First, we will restructure the banks which are dangerously unstable, then we will raise the seafront, transform it into an urban landscape, complete with parks and buildings, revamp historic elements, and develop others, more in line with the evolution of uses; it is a very long-term project with multiple stakeholders.
PS: The “Doughnut Economy” is an economic system, developed by Kate Raworth, based on the preservation of the environment and the urgency of human needs. The idea is to maintain a balance between our needs and available resources rather than pushing growth at all costs.
Merci Arthur !