Strategy is a means to an end: favorable business outcomes. Whenwe think about strategy, we tend to think about planning: study your situation, define a goal, and draw up a step-by-step path to get there. For a long time, planning was the dominant approach in business strategy—in both the boardroom and the classroom. But effective business strategy has never really consisted of just this one approach. The multidecade plans that oil companies make would feel inappropriate to the CEO of a software firm that faces new products and competitors every day and that therefore adopts a more fluid and opportunistic approach to strategy.