The princess-to-be wore Italian designer Luisa Spangoli on her St. Andrews visit

Credit: WeirPhotos/Splash News Online

Nothing like a future princess wearing your clothing to generate worldwide buzz.

The latest designer to land this honor? Luisa Spangoli, the Italian label that crafted Kate Middleton‘s red suit, which she wore while strolling the streets of St. Andrews last month.

Kate purchased the much-admired belted wool ensemble from Hollie de Keyser, a boutique in London s Knightsbridge – her shopping stomping ground.

PHOTOS: Kate Middleton’s 10 Style Essentials

“She looked stunning, and we are proud and flattered that a style icon for women of all the world like her has worn Luisa Spagnoli,” managing director Nicoletta Spagnoli tells PEOPLE. “The color red is perfect for her brunette hair and pale skin.”

The label – known for classy daywear and fashionable and flattering knits – is a family business that dates back to 1928. And this is not their first brush with international celebrity: Sophia Loren modeled for the company s catalogue in 1962.

“My wife Hollie discovered [Luisa Spagnoli] when she was in Italy,” says prominent London fashion distributor Robert de Keyser. “They are hugely successful there. It’s a hidden nugget in fashion, and Kate Middleton picked up on it.”

Now that the secret’s out, how will the company fare? The label is considering distribution in the U.S. Until then, fashion followers will have to travel to Europe to purchase Luisa Spagnoli.

And if the soar in demand for designer Issa (whose royal blue dress is nearly as famous as the future princess herself) is anything to go by, Middleton’s St. Andrews walkabout will prove to be this designer s red letter day.

Please note: Comments have been suspended temporarily as we explore better ways to serve you. Your opinion is important to us; you can find current discussions at