(MONEY Magazine) – Used to be, when fall rolled 'round, you were expected to give to just one charity at work—United Way. But these days you're probably bombarded with appeals from colleagues in charitable walkathons, bikeathons and the likeathons. Feeling overwhelmed by all the extended palms? Here's how to handle today's dogged do-goodniks.

A plan to say no. To avoid looking heartless, have a firm philanthropic plan, so that you have the option to politely decline no matter who knocks. Of course, if you like the person and his or her charity, consider giving. But if you don't like one or the other, suggests Peter Post, author and great-grandson of etiquette doyenne Emily Post, simply say: "I already give to three organizations that are dear to my heart and I don't have the budget to give any more this year."

Except when it's the boss. Sears and others are outlawing solicitations from management, but high-pressure fund raising still happens. If that's true in your office, you've little choice but to give."You don't know what kind of scorecard the boss is keeping," sighs Michael Hoffman of the Center for Business Ethics at Bentley College.

No need to overdo it. Even when the boss is shaking the tin cup at you, be restrained. Thanks to the Net, most pledges are confidential, so give only what feels right. (See below.) "If your boss wants to know how much you're in for," adds Dilbert cartoonist Scott Adams, "ask what he gave. That'll make him go away." —NICK PACHETTI

Most Americans donate as much as $300 a year to three charities at work. The very generous among us give about 1% of our gross income.