Some of the biggest changes have been in the process of generating business strategies—what I call strategy work. Around 1980, the received wisdom was to decentralize into business units, which would each generate a strategic plan. These plans were then amalgamated up the hierarchy, in some portfolio way, for senior management. That approach has all but disappeared, and we've seen a dramatic recentralization of strategy work.

Response to the question: "You've been teaching about, researching, and consulting on business and corporate strategy for 35 years. What changes have you seen in that time?" - "McKinsey Quarterly interview," 2007