The F-16 fighter jet is, as supersonic military aircraft go, a modest machine. It measures just 49 feet long and 31 feet wide from wingtip to missile-capped wingtip, and it weighs about half as much as its U.S. Air Force predecessor, the F-15. With a top speed of 1,350 MPH, it lags the F-15 and other big planes. It can't fly as high or as far. But in battle, the F-16 defies physics. Its design allows extreme maneuvers, even at low speeds. It dumps and regains energy in an instant, and despite its light weight, it can withstand nine times the force of gravity -- which enables some serious twisting and rolling. Pilots jag and flip with subtle nudges to a sensitive electronic flight-control system. The plane is unthinkably agile. Picture a young Michael Jordan with 29,100 pounds of thrust.

Now think of your company: Is it an F-16 or an Aeroflot turboprop? In business, success isn't simply a matter of being quickest to market, of spending the most, or of selling the highest-quality products. You can win by using any of those methods but only if you do one thing more: Outmaneuver the other guy. You have to decode the environment before he does, act decisively, and then capitalize on his initial confusion by confusing him some more. Agility is the essence of strategy in war and in business.

John R. Boyd knew this. He knew it instinctively in the early 1950s when, as a young U.S. Air Force fighter pilot -- cocky even by fighter-pilot standards -- he issued a standing challenge to all comers: Starting from a position of disadvantage, he'd have his jet on their tail within 40 seconds, or he'd pay out $40. Legend has it that he never lost. His unfailing ability to win any dogfight in 40 seconds or less earned him his nickname: "40 Second" Boyd.

Boyd applied his intuitive understanding of energy maneuverability to the study of aeronautics. In the 1970s, he helped design and champion the F-16, an aluminum manifestation of everything he knew about competition. Then he focused his tenacious intellect on something grander, an expression of agility that, for him and others, became a consuming passion: the OODA loop.

Observation; orientation; decision; action. On the face of it, Boyd's loop is a simple reckoning of how human beings make tactical decisions. But it's also an elegant framework for creating competitive advantage. Operating "inside" an adversary's OODA loop -- that is, acting quickly to outthink and outmaneuver rivals -- will, Boyd wrote, "make us appear ambiguous, [and] thereby generate confusion and disorder."

The product of a singular, half-century-long journey through the realms of science, history, and moral philosophy, Boyd's ideas both augment and challenge conventional thinking about organizations and conflict. Boyd himself, a cigar-smoking maverick, enjoyed distinctive unpopularity in official Pentagon circles. But even among critics, his OODA loop was much harder to dismiss.

The concept is just as powerful when applied to business. The convergence of rapidly globalizing competition, real-time communication, and smarter information technology has led to a reinvention of the meaning and practice of strategy. What do you do in the semiconductor industry and other sectors where the time advantage of proprietary technology is collapsing even as the cost of developing it explodes? Companies in manufacturing, telecommunications, retail -- in nearly every business -- are discovering that fashion, fad, and fickle customers require constant vigilance and adjustment. We operate in a video-game world where time is compressing, information goes everywhere, and the rules of the game change abruptly and continuously.