A means of providing corporations with an analysis of their competition and determining strategy, Porter's five-forces model looks at the strength of five distinct competitive forces, which, when taken together, determine long-term profitability and competition. Porter's work has had a greater influence on business strategy than any other theory in the last half of the twentieth century, and his more recent work may have a similar impact on global competition.

Michigan native Michael Porter was born in 1947, was educated at Princeton, and earned an MBA (1971) and Ph.D. (1973) from Harvard. He was promoted to full professor at Harvard at age 34 and is currently C. Roland Christensen Professor of Business Administration at the Harvard Business School. He has published numerous books and articles, the first Interbrand Choice, Strategy and Bilateral Market Power, appearing in 1976. His best known and most widely used...