David Aaker, professor emeritus of marketing strategy at the Berkeley-Haas School of Business and the vice-chairman of Prophet, is the winner of four career awards for contributions to the practice and science of marketing. He has published more than 00 articles and 15 books, which have sold more than a million copies. They include Strategic Market Management, Building Strong Brands, Brand Leadership (co-authored with Erich Joachimsthaler), Brand Portfolio Strategy, From Fargo to the World of Brands, Spanning Silos, and his latest book, Brand Relevance: Making Competitors Irrelevant, which was named to three best book lists for 2011. Named as one of the top five most important marketing/business gurus in 2007, Aaker has won awards for the best article in the California Management Review and (twice) in the Journal of Marketing. A recognized authority on brand strategy, he has been an active consultant and speaker throughout the world and is a columnist for AMA’s Marketing News. Aaker regularly blogs at davidaaker.com and HBR.org.