Tim Brown was vice captain of the Wellington Phoenix soccer team in New Zealand nearly a decade ago when he began thinking about a second act after his sports career. He was interested in design, particularly footwear. And being a Kiwi he also had a particular fondness for wool (New Zealand is home to some 27 million sheep).

Why had such a renewable and biodegradable textile never been used to make footwear, Brown wondered?

The idea of wool shoes might sound strange, not to mention hot and scratchy. But Brown believed he was onto something, and his passion eventually attracted a likeminded partner, Silicon Valley engineer Joey Zwillinger. Their vision has since turned into a formidable natural shoe brand called Allbirds that’s not only disrupting the footwear industry with its comfortable, all-natural wool shoes, but is putting sustainable fashion on the map in a big way.

Remarkable second act

The road to success wasn’t without some sharp curves. Brown retired from soccer in 2012 and enrolled in business school. He remained intrigued by the idea of using eco-friendly wool to make shoes, impressed by its natural ability to resist water, minimize odors and regulate temperature. As he claims in the video below, “It’s the world’s most miraculous fiber.”

After researching ways to make his footwear, Brown launched a Kickstarter campaign in 2014 to begin production. Orders were so strong that he had to shut down the crowdfunding campaign until he could figure out how to meet the high demand.

About that time, Brown’s wife introduced him to a college friend in Northern California whose husband, Zwillinger, was struggling to market renewable algae oil as a replacement for petroleum.

Brown immediately bonded with Zwillinger over a home-cooked meal and a shared entrepreneurial interest in green products. The two decided to team up and launched Allbirds in 2016.

Simply sustainable

Tim Brown and Joey Zwillinger Screenshot of New Zealand soccer star Tim Brown (left) and renewables entrepreneur Joey Zwillinger, co-founders of Allbirds. (Photo: Allbirds)

The duo’s startup is a socially and environmentally responsible certified B Corporation. Incidentally, the name comes from Zwillinger’s love of birding and the phrase, “It’s all birds,” which explorers supposedly uttered when they first arrived in New Zealand.

Allbirds shoes are designed without logos, labels or special detailing. They’re constructed from ZQ-certified merino wool (meaning sheep are raised sustainably and humanely according to strict standards). The wool is specially knitted into a superfine weave — each fiber is about 20 percent the width of a human hair — so it’s not scratchy.

Washable insoles also are formed from merino wool fabric, and soles are green polyurethane made from castor bean oil. The idea was to create something not only sustainable but breathable, durable, comfortable and all-purpose. “If you were going to design one sneaker and only one, what would it look like? We focused on this idea of a singular solution,” Brown notes in this New York Times article. “The right amount of nothing.”

Allbirds are made for men and women and come in several catchy colors like moss and mint. They’re also designed to be worn without socks. The company currently offers two styles: sneaker-like Wool Runners and slipper-like Wool Loungers. All cost $95.

Allbirds Wool Runners Allbirds are designed to be worn almost anywhere and without socks, a winning combination that’s captivating celebrities and Silicon Valley hipsters alike. (Photo: designmilk/flickr)

Shoes are available online and at the company’s two cool, customer-centric retail locations in San Francisco and New York. The newly opened New York store, located in SoHo, actually features a giant hamster wheel for humans that allows customers to hop on and try out their shoes before buying.

A generic shoe for every occasion

Minimalist and machine-washable, Allbirds shoes have caught on not only with hipsters but also with celebrities like Ryan Gosling, Emma Watson and Matthew McConaughey.

They’ve even become de rigueur in Silicon Valley where comfortable conformity is the norm. Allbirds are increasingly part of the standard-issue techie uniform — jeans, t-shirts and hoodies — long favored by engineers, programmers, digital designers and venture capitalists.

This video explores Allbirds’ Silicon Valley appeal.

Brown and Zwillinger plan to keep upending the shoe industry by expanding the company’s brick-and-mortar presence (in direct contradiction to current retail trends) and stretching its global reach. They’re also exploring additional types of natural materials and considering a kid shoe line. Ultimately, the co-founders hope to accelerate the greening of the apparel industry.

As Zwillinger notes in this 2016 interview, “We are at a moment in time when consumers are incredibly open-minded to learning (and buying) from brands, particularly small, upcoming brands that are doing things the way things should be done. And if we can educate people about raw materials sourcing, about beginning of life, end of life of footwear, there’s a great chance that other brands will follow on — in footwear but hopefully beyond that, too.”