Strategy is not complex. But it is hard. It's hard because it forces people and organizations to make specific choices about their future -- something that doesn't happen in most companies. Now two of today's best-known business thinkers get to the heart of strategy--explaining what it's for, how to think about it, why you need it, and how to get it done. And they use one of the most successful corporate turnarounds of the past century, which they achieved together, to prove their point. A.G. Lafley, former CEO of Procter & Gamble, in close partnership with strategic adviser Roger Martin, doubled P & G's sales, quadrupled its profits, and increased its market value by more than