When Rent the Runway first launched in November 2009, it was a hit; it revolutionized the way women dressed (and spent) for special events and formal affairs. With designer gowns typically costing $1,000+, the notion of borrowing a piece for a fraction of the price was exactly what the style world needed.Years later, RTR is still popular, no doubt. Its selection of high-end labels, however, isn't as extensive as its customer base . And for those who veer toward the brand-savvy end of the fashion spectrum, that site was, until nearly a year ago, still lacking.Last November, Alexandra Lind Rose and Trisha Gregory's concept of Armarium was first introduced in the form of a pre-holiday pop-up at the mega-fancy St. Regis hotel in New York, followed by similar events in Aspen for New Year's Eve and Los Angeles for awards season. By spring, the company officially launched as an invite-only app with a Manhattan showroom for users in need of luxury in a pinch. (It would open up to the public in June.) A big selling point — aside from its very high-end inventory — was its " Armi ," a squad of 400 recognized members of the fashion flock to provide styling tips and suggestions for users. By May, Racked reported, Armarium had raised $1.25 million in seed funding. Now it has a full-fledged website, as well as a partnership with Net-A-Porter, allowing shoppers to borrow an item before taking the full-price plunge.Luxury pieces, of course, mean prices are of luxury caliber, too ( according to its site , rental prices are about 12% of the retail price, meaning a $2,495 Vera Wang gown goes for $400, and a $2,970 Marchesa clutch costs $250). Sure, they may be a fraction of the original number, but they're still steep. So why would someone opt into Armarium for a couple hundred dollars instead of some of the other clothes-lending sites, like RTR, currently available? Here's a few choice scenarios: You're a fashion-obsessive going home for the holidays, and your family just doesn't "get" why you can't wear the same black dress to this year's gathering; you're going to your 10-year high school reunion and want people to think you're way fancier than you actually are (let's be real, we've all had a case of the Romy and Michele's); you have a wedding, bar mitzvah, benefit, or who knows what, and you want to feel extra-special but your bank account says, "Hmm, I think not." Basically, Armarium is for those moments you couldn't imagine wearing anything but the look of your dreams; and though the overall price is more expensive than you might anticipate for an item you're only borrowing, not buying, it sure as hell beats dishing out thousands for a dress you might wear only once.And what about the logistics? The standard borrow timeline is four days (each additional day costs $50). You can make reversible alterations to the pieces, and you can reserve a piece up to three months in advance. If something doesn't fit, Armarium will give full credit if it’s returned within 24 hours, and they'll try to get another size or similar style to you before your event (to ensure proper fit, an Armarium representative will liaise with the client prior to sending). If you're in the New York area, however, I recommend making an appointment to visit the Armarium showroom, where you can actually try things on before committing."As fashion insiders in the industry, we have access to so many statement pieces that we see on the runway that don’t make it into production, or are maybe harder to sell ’cause they’re a one-hit wonder, but are cooler to wear," Gregory says. "The question was: How can you kind of create a shared-economy model for luxury fashion that really wasn’t out there, but also position it as a styling service? I think right now celebrities are afforded that; they hire a stylist to get them borrowed looks from the best houses. So how can we give that access to more women out there?" She notes that exposing lesser-known designers — citing Marco de Vincenzo and Alessandra Rich as examples — to the masses is part of the process; it's not just about giving women access to clothing, it's about educating them on brands they may not know.Today's Armarium selection features a solid mix of popular icons — houses like Emilio Pucci, Missoni, Nina Ricci, Salvatore Ferragamo, and Sonia Rykiel — and more up-and-coming labels like Chris Gelinas, Isolda, Novis, and Vika Gazinskaya. Different curated "stories" rotate through the homepage (this week you'll find "Night on the Town" and "Fall's Romance," among others), with new pieces rotating in about every two weeks. "We try to rotate product for the stories, depending on the content we put on the site," Gregory says. "We’ll have a rotating roster of vintage partners, and then we buy four times a year. Within that, different collections come in, whether it be one-off partnerships or collaborations," she continues, noting that the selection will always be on trend, in season, and never stale."I think a lot of those platforms, including us, are focused on the millennial..the upper millennial, the aspirational consumer, who is approaching retail in a different way," Gregory explains when asked who exactly is #JoiningTheArmi . "And we don’t know exactly what that different way is right now, but it’s certainly non-traditional. And how can we introduce that millennial or aspirational client to full-price luxury brands through this service, as opposed to just finding it at a discount site or at an outlet, or just buying accessories or eyewear or fragrance from those brands. I think that’s what we seek to do for that client."