The beauty of ethnography, say its proponents, is that it provides a richer understanding of consumers than does traditional research. Yes, companies are still using focus groups, surveys, and demographic data to glean insights into the consumer’s mind. But closely observing people where they live and work, say executives, allows companies to zero in on their customers’ unarticulated desires. “It used be that design features were tacked on to the end of a marketing strategy,” says Timothy deWaal Malefyt, an anthropologist who runs “cultural discovery” at ad firm BBDO Worldwide. “Now what differentiates products has to be baked in from the beginning. This makes anthropology far more valuable.”
Andrew Hinton 
One approach to quickly doing ethnographic inquiry makes use of a team of researchers and is called Rapid Assessment Process (RAP). Results can be produced in as few as five days but usually takes longer. For more information see http://www.rapidassessment.net