From tech giants Steve Jobs and Mark Zuckerberg to legendary fashion designer Karl Lagerfeld, some of the world’s most successful people have been known to wear the same outfit to work every single day.

In many cases, these distinctive “work uniforms” have become synonymous with the person.

Here are nine famous work uniforms, from Steve Jobs’ black turtleneck to Karl Lagerfeld’s white collared shirt, black jacket, and black sunglasses.

Steve Jobs, co-founder and former CEO of Apple, is perhaps one of the most famous people to adopt a “work uniform.”

Jobs was almost always seen wearing his signature black turtleneck, jeans, and sneakers. He once said in an interview that he owned about 100 black turtlenecks made by Japanese designer Issey Miyake.

Another tech titan, Facebook CEO Mark Zuckerberg, is known for his recurring outfits. In Zuckerberg’s case, it’s usually a black or navy hoodie …

… which he sometimes removes to reveal a gray t-shirt. The t-shirts are reportedly special ordered from Brunello Cucinelli, and reportedly cost between $300 and $400.

Karl Lagerfeld, the legendary designer who died on February 19, 2019, was known for his iconic uniform of black sunglasses and a tailored black jacket with a high-collared, highly starched white shirt. He usually accessorized with some jewelry and gloves.

Lagerfeld reportedly had 1,000 of the same white shirt.

Condé Nast Artistic Director and Vogue Editor-in-Chief Anna Wintour’s distinctive look includes her sleek bob and black sunglasses.

Wintour typically also wears “a patterned or textured skirt, a simple close-fitting jewel-neck sweater and a chunky necklace,” as Annette Tapert noted in the Wall Street Journal.

Elizabeth Holmes, the former CEO of Theranos, before she was charged with “massive fraud” by the SEC and then indicted by a grand jury on “wire fraud schemes,” was known for wearing a familiar work uniform.

Holmes was always seen wearing a black turtleneck like Jobs, which later became a symbol of her alleged fraud. “Such an individual uniform has a risk if you don’t live up to the promise,” fashion critic Vanessa Friedman wrote in the New York Times.

Former Secretary of State and presidential candidate Hillary Clinton made pantsuits her work staples years ago.

She often wears them in bright colors and occasionally in bold patterns.

Fashion designer Giorgio Armani’s work uniform is simple yet streamlined.

He is nearly always seen wearing a navy sweater, navy pants, and white sneakers.

Author and public speaker Fran Lebowitz almost exclusively wears a uniform that comprises a jacket (usually designed by Anderson & Sheppard), a men’s shirt, Levi’s jeans, cowboy boots, and tortoiseshell glasses.

“I have all my suits and jackets made, but I’ve never had a shirt made … it’s not as important to me that they fit perfectly,” Lebowitz told Elle in a 2015 interview.

One of the most famous proponents of the “work uniform” is former president Barack Obama.

“You’ll see I wear only gray or blue suits,” he told Vanity Fair in a 2012 interview. “I’m trying to pare down decisions. I don’t want to make decisions about what I’m eating or wearing. Because I have too many other decisions to make.”

In fact, experts say making lots of small decisions like what to wear and what to eat throughout the day can drain your mental energy for when you need to make more important decisions. It is perhaps this “decision fatigue” that drives so many successful people to adopt work uniforms.

Originally published on Business Insider.

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