The New York Times sent its staffers a stern warning yesterday: Don't send any naughty e-mail.

To make sure everyone was paying attention, the Times disclosed that it has just fired more than 20 employees for sending "inappropriate and offensive" e-mail messages.

The news was delivered, logically enough, in an e-mail from Russell Lewis, the Times Co.'s president and CEO, and Cindy Augustine, a senior vice president.

"Please remember that our e-mail system is primarily a tool for business communication," the executives said. "While a reasonable amount of personal e-mail is permitted, communication still must meet the standard described [in the memo]."

The staffers who were pink-slipped are not journalists. They work in the company's Shared Services Center in Norfolk, which handles payroll, benefits, invoices and the like.

Times spokeswoman Nancy Nielsen said this is not the first time the company has fired people for questionable e-mail, but that previous dismissals involved isolated instances of misbehavior.

Nielsen said staffers were sent the memo as "a reminder of what our e-mail policy is, and mentions this incident so the company isn't filled with rumors and they have the information. You could imagine how this could turn into 10 false stories."

While perhaps not surprising in an age when Bill Gates's past e-mail is read in court, the warning caused a stir among some Times reporters who increasingly depend on electronic communications to do their jobs.

Robert Gellman, a privacy consultant here, said that "there's a lot of employee monitoring" in corporate offices. "There's a lot of software expressly designed to monitor what people do on their computer," he said.

"The law says you can monitor e-mail. How many employees routinely know about it, think about it? I don't think people are generally aware. For a significant percentage of company e-mail users, this will be a revelation."

Marc Rotenberg of the Electronic Privacy Information Center said that such monitoring is "a lot more common than it should be." The question, he said, is "whether you leave your privacy when you enter the electronic workplace."

In their memo, Lewis and Augustine say that "while the company does not routinely monitor the e-mail communications of employees, we do investigate when a violation of the company's e-mail policy is reported." That's what happened at the Norfolk center, they say, where some staffers "received disciplinary warning letters" in addition to the more than 20 who were fired.

Times policy says that e-mail communication "must be consistent with conventional standards of ethical and proper conduct, behavior and manners and are not to be used to create, forward or display any offensive or disruptive messages, including photographs, graphics and audio materials." The paper's policy against "sexual and other harassment or discrimination" also applies to e-mail.

The staffers fired at Norfolk, say Lewis and Augustine, "all transmitted clearly inappropriate and offensive material, which left no doubt as to the discipline required. . . .

"If you receive e-mail that violates our policy, please notify your manager or the head of Human Resources in your business unit. We will take prompt action to address the situation."

The executives also asked that "drafts of news reports, news articles or other work" be deleted within 30 days of publication. In the event of a lawsuit, they say, the Times "could have a legal obligation to disclose all messages, including such 'deleted' messages."