The founders of Gilt Groupe reveal how they built the Web's most famous fusion of high tech and high fashion.

For years, sample sales have lured fashion insiders to makeshift storefronts in anonymous locations, offering dramatic, fleeting bargains on coveted designer brands. For those lucky enough to make an exclusive e-mail list, a Marc Jacobs or Hermès sample sale is a drop- everything-and-run event.

Harvard MBAs Alexis Maybank and Alexandra Wilkis Wilson, best friends and dedicated sample sale shoppers, saw the industry-changing potential of taking sample sales onto the Internet. In November 2007, they launched their members-only Web site to a select national group of thirteen thousand young, high-end shoppers. They offered 50-70 percent off luxury brands like John Varvatos and Valentino, in "flash" sales lasting just thirty-six hours. It became an immediate viral hit as members rapidly invited friends to join. In four short years, Gilt Groupe has spawned dozens of imitators and grown to five million members and has a valuation of $1 billion.

Maybank and Wilkis Wilson explain how they launched a simple yet groundbreaking business that catered to their passions. They provide straight talk on how to build a start-up and negotiate the conundrums that still face women in business. For Gilt customers interested in an inside view of the fashion industry, they also provide a revealing portrait of key players like Zac Posen, Christian Louboutin, Valentino, and many others.