When Cindy Casselman took a communications job at Xerox headquarters in Stamford, Connecticut, the company's communications weren't so good. If Xerox made a big acquisition or had a disappointing quarter, many of its 85,000 people read the news in the papers before they got the scoop from the company. Casselman was determined to change things. "I was manager of employee communications," she says. "I took my job seriously."

But Casselman, now 50, didn't have much formal authority. She was, to use an out-of-favor phrase, a middle manager: someone whose boss had a boss who had a boss. So she assembled a makeshift budget and mustered a volunteer team that she called the Sanctioned Covert Operation (SCO) - "sanctioned," because her direct boss tolerated what looked like a modest project; "covert," because her actual goals were more ambitious than she let on.

Today, thanks to the SCO, any Xerox employee can visit the WebBoard, the company's spirited intranet site, and talk to other employees, read up-to-the-minute news about internal developments - and in general get more connected to what's happening inside this vast enterprise. How did Casselman have such a big impact with so few resources? She had a knack for playing politics.

Chris Newell, 47, is founder and executive director of Lotus Institute, a 20-member unit of Lotus Development Corp. (based in Cambridge, Massachusetts) that develops solutions using Lotus Notes software. It's a fun and interesting job - but hardly a position of power. "We generate new ideas about how software interacts with culture," he says. "We're the shrinks of shrinkwrap."

Last year, Newell became convinced that the emerging field of "knowledge management" represented a big market opportunity for Lotus and its parent company, IBM. So he became a major catalyst behind a series of knowledge-management products that Lotus and IBM began to roll out by the end of the year. Newell didn't have the authority to order such initiatives. But he did know how to play politics.

About three and a half years ago, when the Discovery Channel wanted to extend its high-profile brand beyond cable TV, CEO John Hendricks assembled a committee to explore interactive television. Tom Hicks, now 44, thought the company should focus on the Internet. But this was 1994, when pundits were heralding interactive TV and the Net was still an unproven medium. Worse, Hicks ran the division that produced Discovery's magazines. Today the Discovery Channel Online is a much-celebrated presence on the Web. And when was the last time you watched interactive TV? Pushing for this mid-course correction wasn't easy. It meant playing politics.

Office politics. Just say the words, and you sense the disdain. Isn't "playing politics" a tool for people who can't get ahead on merit - who pursue their own agenda regardless of what's good for their colleagues or the company? That's the downside of office politics. But what about the upside? Office politics is a lot like "real" politics. Plenty of politicians launch campaigns simply because they relish the privileges of power. But at least some politicians campaign for things that matter to people other than themselves. Dismissing all political campaigns as cynical and self-aggrandizing becomes a self-fulfilling prophecy. The same goes for office politics.