Book excerpt: Now available in paperback, with an all new Reader's guide, The New York Times and Business Week bestseller Co-opetition revolutionized the game of business. With over 40,000 copies sold and now in its 9th printing, Co-opetition is a business strategy that goes beyond the old rules of competition and cooperation to combine the advantages of both. Co-opetition is a pioneering, high profit means of leveraging business relationships. Intel, Nintendo, American Express, NutraSweet, American Airlines, and dozens of other companies have been using the strategies of co-opetition to change the game of business to their benefit. Formulating strategies based on game theory, authors Brandenburger and Nalebuff created a book that's insightful and instructive for managers eager to move their companies into a new mind set.