Like most women, Katie Murphy has fluctuated in clothing size over the years, usually falling somewhere between a 12 and 14. And, also like most women, she's grown weary.

A native Houstonian who grew up worshipping at the altar of Tootsies and the Galleria, she recalls discouraging shopping trips with her mom during visits back home: "I'd find a couple of very well-edited, interesting boutiques, but I could never find anything in my size," she says. The problem persisted outside Houston, too. "I'd go shopping with my girlfriends and not be able to try stuff on or end with, like, a T-shirt. It's not fun, and years and years of that gets in your head."

Murphy's not alone. In fact, she's in the majority, as recent data indicates the average American woman wears a size 16-18—at least one whole size up from the widely reported 14, a now outdated statistic some in the industry seized onto in an effort to "diversify" their product lines over the last decade.

Somehow, though, that generally meant extending to a size 12—if that. And most luxury designers aren't even cutting above a size 10, a fact that made things even more frustrating for a self-described fashion aficionado like Murphy, who loves labels like Roland Mouret: "one of my favorite designers that I could never fit into," she says.

But, thanks to 11 Honoré, "Now I can." Murphy is head of client services for the e-tailer that offers—sometimes exclusively—designer clothing in sizes 10-20 and up. Think of it as a sort of budding Net-a-Porter for extended sizing, anchored in New York and L.A. with customers across the country (including many here in Texas).

Founded just two years ago, the growing company has about 25 employees, but it feels disingenuous to call it a start-up: What began as a pitch to a handful of designers to extend their sizes has rapidly evolved into collaborations with more than 80 high-profile, high-fashion labels, from Prabal Gurung to Texas darling (and Lady Gaga fashion director) Brandon Maxwell, both early adapters to the 11 Honoré concept, Murphy notes.

"The original business pitch two years ago was us going to designers being like, 'Hey, Brandon Maxwell, listen: Your stuff is awesome. Think how much better you could service women across the world if you cut above a size 10.' And Brandon was like, 'hell yeah.' He gets it," she says. "That's how we started. Now we're fielding pitches. Designers are calling us."

Indeed, major fashion houses like Dolce & Gabbana and Stella McCartney are jumping on the bandwagon and will soon release collections with 11 Honoré—to which we say, better late than never. "We are bringing on brands with more equity across the market," Murphy says, but there's also major satisfaction in the somewhat introductory role 11 Honoré plays for a client when it comes to smaller brands. "She's seeing Eileen Fisher, she's seeing Lafayette, she's seeing Akris—which is all great, but..." Murphy trails off, but we can finish her thought: there's so much more—an entire world that historically excluded the average American woman, lest she have the resources to facilitate a costly, custom-made wardrobe.

Things are getting better, to be sure—11 Honoré even opened New York Fashion Week this year—but there's still some concern that size inclusivity, much like "going green," is just trendy. "This is not a moment—it has to be a movement," Murphy says. "I understand movements have to start with a moment, but it has to be the new normal."

Though 11 Honoré is based online, Murphy plays an important role IRL. "We had a beautiful platform with beautiful clothes, but we realized specifically with this clientele that we had to meet them in real life," she says. "We could show side-zip pants online, but no one was buying them because they automatically thought they wouldn't look good."

Women of any size will attest that online shopping can be a game of roulette, but for those conditioned to believe elements like, say, horizontal stripes or side-zippers render certain garments simply off-limits, a total shift in perspective means unlearning some long-held assumptions.

That's what brought Murphy back home to Houston last month for a private trunk show, where she introduced local clients to some of 11 Honoré's seasonal inventory like a striking JC Obando skirt suit and a slinky leopard number from Adam Lippes.

"There's a lot of hesitation at first, because these women are automatically set up to think, when I go into a fitting room, nothing fits. It's kind of getting over that objection and that hurdle," Murphy says. "But once you do, you develop the most loyal customer ever. They genuinely feel confident and beautiful. They're not being put in only muumuus or caftans—they're actually being taught how to dress to see their shape, to wear prints and colors and things that were previously stigmatized for a curvier woman."

Witnessing that realization, Murphy says, is the best part of the job, and she hopes to be in Houston more often—at least once a season—to connect with top clients here. "It's very emotional, but it's also so gratifying and so awesome," she says. "Once they realize it's out there and accessible, there's no stopping them."