THEY’RE NOT ADORNED with a bold logo or blingy hardware, but Maison Bonnet’s glasses still make a strong statement. Take, for example, the Saint Laurent 1980 style, originally created for designer Yves Saint Laurent, who was a loyal client for decades. The frames are oversized but not overwhelming, with a curved silhouette that brings to mind an elegant piece of midcentury furniture or museum-caliber sculpture instead of a mere accessory. Their purpose isn’t just to help you see, but to become a distinguishing feature of your face, an expression of refinement and taste.

Maison Bonnet traces its roots back to the 1950s, when Robert Bonnet founded the company after being trained by his father, Alfred, a French eyewear craftsman. The brand offers a wide selection of signature styles, some named after famous legacy clients, from the architect Le Corbusier to Jacqueline Kennedy Onassis. Aristotle Onassis wore Bonnets too, as did his paramour, the opera singer Maria Callas. All the brand’s glasses, for both sun and vision, are made from scratch and shaped by hand to create the perfect style and fit, physically and emotionally, for each client’s face.

That handcraft happens, as it always has, in a workshop on the property where the family lives, in the Pays d’Othe region of France, about a two-hour drive southeast of Paris — literally, Maison Bonnet. The process itself, which includes a second fitting for tweaking in person, admittedly isn’t quick. Acetate frames take about three months to produce, Buffalo horn takes about three and a half months, and extra-rare tortoiseshell, made from a stash purchased long before the material became restricted, requires closer to nine.

Customers, who come from around the world, don’t seem to mind the wait. “We have a steady clientele, and they’re used to having bespoke things,” Franck Bonnet says. “They’re used to waiting.”

Last year, the Bonnet family acquired another French eyeglass brand with an illustrious heritage: L’Ingénieur Chevallier, which was founded in 1740 as the first optician in Paris and has created eyewear for several kings. The selection at L’Ingénieur Chevallier’s two Paris boutiques includes its own pieces — often archival designs made in small quantities by hand — and frames from kindred-spirit labels such as Yuichi Toyama and Hoffmann. The L’Ingénieur Chevallier staff has been trained in Maison Bonnet’s obsessive rituals for a precise fit.

Both companies tend to attract discerning customers — the French architect India Mahdavi and beauty entrepreneurs David Mallett, François Nars, and Troy Surratt all wear Bonnets — but still, occasionally, a buyer needs persuading. “Sometimes we need to calm the client because they want big glasses,” Franck Bonnet explains. “They want big details, and they forget what is important: It’s the gaze, not the frame.”