In September 1999, Polaroid Corparation introduced to the U.S. market a small, instant camera with a cheap lens that produced fuzzy, postage-stamp-sized photographs that could double as stickers. Scientists and engineers at Polaroid, holding true to the company's long-standing reputation for building high-quality, technologically innovative products, were skeptical. They worried that this new instant camera, called the I-Zone Instant Pocket Camera, would taint their reputation. Before becoming one of I-Zone's ardent supporters, Ed Coughlan thought the camera was crazy, "I'm an old engineer. I couldn't for the life of me figure out who'd buy it" (quoted in Klein, 2000, p. A1).

Figuring out not only who would buy it, but why they would buy it, where they would buy it, how often they would buy it, and how they would use it is the cornerstone of understanding consumer behavior. Consumer behavior is the study of people: how...