Lesley M. M. Blume is a writer and journalist based in New York City, where she was born. The author of three books for Knopf, Ms. Blume has worked for Cronkite Productions, The Jordan Times in Amman, and ABC News Nightline; her articles have appeared in many publications, from Slate to Vogue.

The Gilt Groupe, an online sample sale site, has a million members and caused an epic shopping craze—even in a recession. Why are women so obsessed? By Lesley M. Blume.