Are you situationally aware?

Situational awareness: being aware of what’s happening around you to understand how information, events, and your own actions will impact your goals and objectives.

This is how Wikipedia defines this concept that’s been bandied about a lot lately, since those Northwest pilots got distracted on their laptops and flew wayyyy beyond Minneapolis, their destination. Whatever the rogue navigators were viewing or doing on their mini computer screens, they were oblivious to the world and to their job.

So situational unawareness can be dangerous these days.

I’ve thought about the concept a lot, actually, even before it came into vogue. Walking down Broadway to work each morning, I stare at my BlackBerry, thumb poised on my rollerball. I’m oblivious to traffic, at my peril.

Others around me are oblivious, but immobile. The New York Times recently published a rant on cellphone users who stand in the middle of sidewalks and subway stairways. “This new brand of boor,” the writer called these people. The blog post drew an avalanche of comments from readers.

Situational awareness is a challenge for every leader, from President Obama on down. “The hardest thing about my job is staying focused,” the President told 60 Minutes. And as I pointed out in a Postcard called “How the best bosses find focus,” former CEOs Meg Whitman of EBAY , Anne Mulcahy of Xerox and A.G. Lafley of Procter & Gamble are just a few of the corporate leaders who say that knowing what not to do is as key to success as knowing what to do.

Avon chairman and CEO Andrea Jung, who is on the boards of Apple and General Electric , made this same point to me last week. We were talking about Steve Jobs, actually, and Jung noted that “tightness of vision” has been one of the many reasons Apple consistently stays on course and rarely falters.

And then there’s the master of situational awareness in sports: Derek Jeter, who we’ll see tonight when the Yankees meet the Phillies in Game 1 of the World Series. In a fascinating story about the Yankee captain in the New York Times today, Jeter contends that his success is based on “simplifying things.” He’s better than almost anyone–in baseball, at least–at reducing the clutter that can overwhelm players, especially All-Stars in the spotlight. The story offers lessons for any leader–or anybody aspiring to stay in a job.