Editor's Note: By significantly expanding our understanding of the dynamics of competition, Michael E. Porter's Harvard Business Review article "How Competitive Forces Shape Strategy" launched a business management revolution among academics and practitioners when it was published in 1979. In the just released On Competition, Porter collects his most influential articles from HBR, and adds new work on health care, philanthropy, social responsibility, and leadership.
[This article was provided with permission from Harvard Business School Working Knowledge.]