Philip Kotler was once told, "I thought you were the author of one book (Marketing Management) and 34 versions of it." The man who's been called the "messiah of marketing" smiles as he recalls the incident, but there's an element of truth in that quote.

Marketing has undergone a sea change in the three decades since Kotler's first book - now considered a Bible for all marketing management students - hit the stands. Today, Kotler says he would be embarrassed if someone asked him to autograph the first edition of the bestseller.