How would you feel if your partner suddenly announced that he had found a dream home in one of the chicest parts of Paris, with tons of space for the two of you, your four children, and your rapidly expanding art collection, as well as a killer view of the Eiffel Tower? Delighted? Ecstatic? Not Cecilia Bönström—at least, not when her husband, Thierry Gillier, told her two years ago that he was planning to buy just such a place, on rue Galilée, one of the elegant streets running south of Avenue des Champs-Élysées.

“Thierry is always looking for new homes,” Bönström says, throwing a teasingly reproachful glance at him. “He’s the same with everything he does: always looking for the next thing. I loved our old home. It was beautiful, had a wonderful history, and I didn’t want to leave.” And no wonder. Why would anyone choose to abandon an apartment that was originally designed as a bachelor pad for Baron Haussmann, the redoubtable city planner who transformed Paris in the mid 1800s? “There was a music room with frescoes of angels painted on the ceiling,” Bönström says. “The angels were named Mozart, Bach, and Beethoven. But Thierry insisted that he’d found somewhere even more special—and, of course, he had.”

Bönström, in front of Christopher Wool’s Untitled, 2006.

Photograph by François Halard.

Gillier, 59, who is the founder and CEO of the global chain of Zadig & Voltaire fashion stores where Bönström, 48, is the artistic director, had discovered a combination of space, light, and vistas in a city that is so densely built that such elements are rare to come by even in the most expensive neighborhoods. The building, designed as a series of apartments surrounding a pretty courtyard garden, sits on a small hill that sets it above its neighbors, allowing for a panoramic view of Left Bank rooftops and the Eiffel Tower from the top floor. “I knew this kind of opportunity wouldn’t happen again,” Gillier says. “And, of course, it gives us much more space for the art.”

Gillier, next to Franz West’s sculpture Innocente (After Cy Twombly), 2011, with Rudolf Stingel’s Untitled, 2010, behind him.

Photograph by François Halard.

A Picasso oil of a woman’s head in subtle shades of pink and gray is the first thing you see when the elevator doors open into Gillier and Bönström’s new home. The surrounding walls are covered with blue-chip works. Here is an enormous Jean-Michel Basquiat painting; there, a Christopher Wool abstract piece and two upside-down portraits by Georg Baselitz painted 35 years apart. An exquisitely delicate oil painting by Cy Twombly—a white papier-mâché sculpture that Gillier placed by the terrace-facing window, as if to guide all eyes toward the open expanse.

The staircase, with Indonesian sculptures on the landing and Günther Förg’s Ohne Titel, 1990, at left.

Photograph by François Halard.

Gillier’s love of art took root when he lived in New York after high school. He studied painting and film at Bard College and spent his free time scouring the city’s museums and galleries. Born in Troyes, in northern France, to a prominent textile family, he moved to Paris after Bard and worked for Yves Saint Laurent before launching Zadig & Voltaire, in 1997. Gillier named the brand after one of his favorite books, the 1747 novella Zadig, or the Book of Fate, by the French writer Voltaire. Zadig & Voltaire soon became known for luxe rock-chic silk shirts and dresses, leather jackets, and strategically torn jeans and T-shirts that have become off-duty celebrity staples. (The New York Times once described Zadig & Voltaire’s look as “Haute Liberal Arts Dormitory.”) The first Zadig & Voltaire store opened in Saint-Germain-des-Prés, in 1997, and there are now nearly 400 stores, in more than 40 countries.

The view from the terrace with pillars from the Gurma people of Burkina Faso.

Photograph by François Halard.

Among Zadig & Voltaire’s early adopters was Bönström, who was born in Gothenburg, Sweden, and moved to Paris to model at the age of 17. After working all over the world in her 20s and early 30s, she decided to pursue a new career in fashion design. “The first time I went into a Zadig & Voltaire boutique, I loved it,” she says. “I loved the clothes, and the way they were displayed.” Having wrangled a meeting at the company in 2003, she made a mood board of her design ideas and was hired as an assistant. Three years later, she was promoted to artistic director. Tall and willowy, with delicate features and feathery blonde hair, Bönström, who is clad in a black mohair sweater and skinny crystal-studded black jeans when we meet, is a perfect ambassador for the brand.

She and Gillier married in 2016 and have a 7-year-old son, Emil, as well as three kids from their previous relationships: Bönström’s sons, Victor, 18, and Nils, 16, and Gillier’s 19-year-old daughter, Manon. “For Thierry, one of the most important aspects of the new apartment was that it should have the right walls in the right places to exhibit the artworks in his collection,” says Bernard Dubois, the young Belgian ­architect who collaborated with Gillier and Bönström on its design. “But for me, the great thing about this place was that it was also for a family.”

Pablo Picasso’s Buste de Femme, 1970, with a collection of plastic Disney dwarves.

Photograph by François Halard.

Gillier built the home in the top two stories of the building and sold the lower-floor apartments; this is unusual in Paris, where anyone lucky enough to be able to carve up a late-19th-century building typically bags the coveted second floor, which generally has the highest ceilings and biggest windows. But Gillier was excited by the possibility of constructing a terrace on the top level, which originally consisted of the tiny maid’s rooms that fill Parisian attics. Both floors had been stripped of their walls, doors, and most other fixtures before he bought the building, but were still linked by a grand stone staircase, which has since been restored. He and Bönström designated the top floor as a social space accommodating the living room, dining room, screening room, and kitchen. The bedrooms, bathrooms, and dens are all below, in the family zone.

Cy Twombly’s Venere Franchetti, 1963, hangs above a collection of 19th- and 20th-century wood-carved masks and figures in the living room.

Photograph by François Halard.

Together with Dubois, the couple ensured that the public and private spaces were designed to look and feel very different from each other. The social area has a utilitarian, postindustrial air, with raw wooden roof beams and floors clad in one of Dubois’s favorite materials, ceppo di gré, a bluish-gray stone found near Lake Iseo, in northern Italy. A gigantic slab of ceppo di gré serves as the center of the kitchen, flanked by gleaming stainless steel units and cupboard doors made from gnarled oak. “It isn’t the best quality oak, but we chose it because the flaws give it character,” Dubois explains. The furniture, meanwhile, was chosen for its stylish comfort. The lounge is dominated by voluptuous Christian Liaigre sofas upholstered in blue and green velvet, and the dining room by mid-century Charlotte Perriand shelving and Pierre Jeanneret chairs. Gillier and Bönström added lighthearted touches, such as the brightly colored plastic dwarves that live under the Picasso.

A view into the dining room with Jean-Michel Basquiat’s The Thinker, 1986, at right.

Photograph by François Halard.

By contrast, the family floor, divided into a series of suites, was reconstructed in Gillier’s favorite architectural style: the imposingly elegant, highly disciplined aesthetic of 17th-century French interiors. “That was the best period for French design and architecture,” he says. “It was the strictest, purest, and most beautiful, with lots of straight lines.” Gillier and Bönström’s master suite was designed to include a hallmark of the period: an enfilade, or series of spaces whose doors are aligned to create a vista of one room leading to another. That sense of visual flow was intensified by the warm American-walnut floors, shelves, and cabinet doors. “Because both floors were empty, we could choose how to lay out the different spaces from scratch,” Dubois says.

Steven Parrino’s Death in America #2, 2005, with a pair of Pierre Jeanneret armchairs.

Photograph by François Halard. Photography Assistant: Clement Vayssieres.

More art hangs in the kids’ rooms, including a series of Steven Shearer screen prints in Manon’s, and a Yngve Holen sculpture of bright blue car doors in Emil’s. Yet the kids’ own personalities dominate their respective spaces. Manon, who is studying art, has set up a table for her work, while Emil’s room is strewn with toys. As for Gillier and Bönström, they enjoyed working with Dubois on the apartment so much that they commissioned him to design a new flagship store for Zadig & Voltaire on rue Cambon before construction had been completed here on rue Galilée.

Now that his family is happily settled, has Gillier finally stopped hunting for new properties? “Never!” he says, laughing, as he points toward a pile of real estate brochures. “And I’d like to make more changes to this place. I’m not completely happy with the lights…”

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