How Does Paris Stay Paris? By Pouring Billions Into Public Housing

The two-bedroom penthouse comes with sweeping views of the Eiffel Tower and just about every other monument across the Paris skyline. The rent, at 600 euros a month, is a steal.

Marine Vallery-Radot, 51, the apartment’s tenant, said she cried when she got the call last summer that hers was among 253 lower-income families chosen for a spot in the l’Îlot Saint-Germain, a new public-housing complex a short walk from the Musée d’Orsay, the National Assembly and Napoleon’s tomb.

“We were very lucky to get this place,” said Ms. Vallery-Radot, a single mother who lives here with her 12-year-old son, as she gazed out of bedroom windows overlooking the Latin Quarter. “This is what I see when I wake up.”

Public housing can conjure images of bleak, boxy towers on the outskirts of a city, but this logement social was built in the former offices of the French Defense Ministry, in the Seventh arrondissement, one of Paris’s most chic neighborhoods. It’s part of an ambitious and aggressive effort to keep middle- and lower-income residents and small-business owners in the heart of a city that would otherwise be unaffordable to them — and by extension, to preserve the ineffable character of a city adored by people around the globe.

This summer, when the French capital welcomes upward of 15 million visitors for the Olympic Games, it will showcase a city engineered by government policies to achieve mixité sociale — residents from a broad cross-section of society. One quarter of all Paris residents now live in public housing, up from 13 percent in the late 1990s. The mixité sociale policy, promoted most forcefully by left-wing political parties, notably the French Communist Party, targets the economic segregation seen in many world cities.