"In this Internet world, we compete with companies that are public," said Mr. Middelhoff, who is intent on competing with nimble rivals like Amazon.com.

The company recently revamped its business to speed product introductions, which should make it more competitive with smaller, more nimble rivals.

Industry giants like United will try to become more like their nimble low-fare rivals, scheduling their flights more efficiently even if it means less convenience for their customers.

No one can be sure that the city's frantic efforts will protect Empire-Detroit from its more nimble rivals forever.

But after Bank One bought it in 1997, First USA stumbled against newer and nimbler rivals.

This inflexibility means that NEC often loses business to more nimble software-only rivals whose products run on a variety of systems.

Yahoo said Tuesday that it was restructuring its operations and shuffling its management ranks amid growing criticism in and outside the company that it had become too bureaucratic to compete effectively against nimbler rivals.

Reuters, the world's biggest publicly traded news and financial information provider, announced its largest loss today, a result of the global economic slowdown that has decimated the market for its stock trading terminals and left the company exposed to cheaper, nimbler rivals.

He said I.B.M., based in Armonk, N.Y., had produced these results in an increasingly competitive computer industry marked by rapid technological change and a growing group of "nimble" rivals.

Sony was long considered one of Japan's most innovative companies, creating the Trinitron TV set as well as the Walkman, but the company has recently trailed nimbler rivals.