The Duchess of Cambridge's go-to shoe designer says a four-inch heel is the key to show-stopping self-assured style.
Rupert Sanderson, the man behind Kate's favourite Malory pumps, says a four-inch heel is the 'sweet spot' for transforming any look.
"Whenever a woman steps into a pair of four-inch heels, something magical happens," he says.
"Her silhouette instantly changes: her head lifts, the small of her back curves, her shoulders broaden slightly and her calf muscles bunch. From that moment she, quite literally, walks taller.
"Any higher a heel, and you're pushing things. Lower, and those silhouette changes don't take place in quite the same way."
The Duchess regularly wears heels on public engagements, and Sanderson says the four-inch heel can be empowering for women.
Writing for the Daily Mail, he explained: "The Duchess uses a stiletto heel as part of her sartorial arsenal in transforming herself from a busy mother into one of the world's most photographed women.
"She's tall, but in heels she becomes commanding, often standing a head above the men in the room."
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And he says that any woman can take a leaf out of Kate's book and see for themselves how the four-inch heel can transform their look.
"Only a woman herself can explain how wearing heels makes her feel, but it's wonderful when a woman comes into my shop wearing lower heels, or a pair of trainers, then, as she puts on heels, she seems to step through a magic portal; suddenly she seems self-assured in a different way," he says.
"My hope is that a four-inch heel will have a place in every woman's wardrobe. They can be empowering; they can change your state of mind."