Brian Spaly: Trunk Club's virtual stylist

Clothes-minded: Trunk Club is Brian Spaly's second apparel venture.

When Brian Spaly jokingly told a girlfriend that his clothes didn't fit well, she gave the Stanford MBA student a sewing machine. He mastered the machine (and business school) and in 2007 began selling pants he had designed out of the trunk of his car. He eventually co-founded men's clothier Bonobos, known for its brightly colored slacks and its novel distribution strategy: It maintains inventory-free storefronts in large cities; customers can try on clothes, but they must buy online.

Creative differences with his co-founder prompted Spaly (pronounced SPAY-lee) to leave Bonobos in 2009, but it wasn't long before he landed a new gig and a new way to reinvent retailing. Investment fund Anthos Capital asked Spaly to sign on as CEO of a company that would deliver a customized box of clothes on demand; clients would buy and keep only the duds they liked. Think personal shopping meets Zappos.

Spaly, 36, agreed to become founder and CEO of Trunk Club, launched in Chicago in 2010. (Anthos had backed an earlier, unsuccessful company, also called Trunk Club, that dissolved.) Just as he did at Bonobos, Spaly is exploiting technology at Trunk Club. He uses Facebook (FB) and Twitter to market the club, mostly to 25- to 50-year-old men who make six figures, and proprietary software tracks customers' measurements and clothing preferences.

But investors say customer service is Trunk Club's edge: "The sales team and stylists are developing relationships daily over a long period of time," says Dana Settle, a founding partner of Greycroft in Los Angeles, which was part of a group that poured $11 million into the company in July 2011. A typical trunk, which can be delivered as often as a customer likes, contains 10 items, averaging $150 per item. Most keep a third of what's sent.

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While there are other subscription fashion services for men (rivals include Frank & Oak and Five Four Club), Trunk Club's niche is guys who are more interested in saving time than saving money. Trunk Club earned $17 million in revenue last year, and Spaly projects sales of $40 million in 2013, which would make the company profitable by the end of the year.

The entrepreneur acknowledges that Chicago isn't where most clotheshorses expect to find a burgeoning fashion business, but after management-consulting stints in San Francisco and Boston and running Bonobos in New York City, the Michigan native is happy to be close to home. "I wanted to come back to the Midwest and create a company in this part of the world," he says. Trunk Club today has 150 employees. Sounds as if Spaly finally has found the right fit.

This story is from the May 20, 2013 issue of Fortune.