Twice most days, she changes her own shoes: flats first thing in the morning, heels once she reaches the office, sometimes back again depending on what the day still has to ask of her feet. It's a small swap, made without ceremony — the kind of decision most people make once and stop revisiting. She has spent thirty years designing shoes that other women wear on their best and worst days, and she still treats her own feet the way she treats a client's: something to be fitted, not flattered.

Sandra Choi was born on the Isle of Wight and spent five years of her childhood in Hong Kong with her grandparents before returning to England and enrolling at Central Saint Martins in 1991. She's often assumed to be the niece of Jimmy Choo himself — the Penang-born son of a Malaysian cobbler, who made his first pair of shoes by hand at eleven and later trained at London's Cordwainers College. She's actually the niece of his wife, Rebecca, a mix-up that's followed her for decades and that she has never seemed especially interested in correcting. She left her degree unfinished after an internship in Choo's London couture workshop turned into the whole plan: by 1996, when the ready-to-wear label launched under his name, she was named creative director, a title she has now held for thirty years.

The division of labor at the label, in those early years, ran along a clean seam: Tamara Mellon oversaw the brand's image, advertising, and the business of getting the shoes onto famous feet, while Choi stayed on product, responsible for what the shoes actually were. It's a split that's easy to misread as glamour on one side and craft on the other, except that craft, in her case, is oddly literal: during fittings, she tests a shoe's comfort across several different feet rather than trusting one wearer's opinion, on the theory that a shoe that only works for one foot shape hasn't actually been solved yet. "If I can do something to make them a bit more comfortable without sacrificing style, I will," she has said of the trade-off she refuses to treat as a trade-off.

She keeps the same instinct for boundaries she keeps for shoe lasts: firm, but not advertised. She holds Friday emails until Sunday night rather than let them ruin someone else's weekend, and she still finds time most weeks for a family lunch she cooks herself. None of it reads as a philosophy when she describes it — just a woman who has decided, thirty years into a job that dresses other people's feet for magazine covers, that her own two pairs of shoes are enough of a decision to make in a day.