As recently as ten years ago, we thought we knew most of what we needed to know about strategy. Portfolio planning, the experience curve, PIMS, Porter’s five forces-tools like these brought rigor and legitimacy to strategy at both the business-unit and the corporate level. Leading companies, such as General Electric, built large staffs that reflected growing confidence in the value of strategic planning. Strategy consulting boutiques expanded rapidly and achieved widespread recognition. How different the landscape looks today. The armies of planners have all but disappeared, swept away by the turbulence of the past decade. On multiple fronts, strategy has come under fire.