"Out, out damned spot!" is surely the most famous instance on record of a woman swearing. But as everyone knows, Lady Macbeth was no lady. For years, the conventional wisdom held that swearing was off limits to women -- any self-respecting woman, that is. But now there are signs that that is changing in today's work place. As long as women abide by certain conventions -- what might be termed "business swearing etiquette" -- they can get away with, and even benefit from, the judicious use of profanity.

This new linguistic license for women has come about because swearing in the work place is reportedly on the upswing among both sexes. The increase has been variously attributed to the trend toward informality, the decline of religion, the heightening pressures in the work place and, among the age group that can remember it, the revolution of the '60s. Whatever the reason, women have simply picked up the language of the locker room while they were learning the game from men. And, as many have found, colorful language often comes in handy.

"Swearing can be very disarming," says Marlin Potash, a New York-based organizational and clinical psychologist. "By swearing, you can convey that someone can level with you, that you won't be shocked, that you won't fall apart under pressure."

Swearing can also add a light touch in tense situations. "Around here we like to say, 'A client is coming -- wear your gray flannels and don't {swear} in the hall,' " says a real-estate investor, who claims this always amuses those female colleagues who feel anxious about defending a substantial investment before representatives of a pension fund.

Indelicacies can also build camaraderie, especially when the butt of the anger is a common enemy -- the office copier or the person on the other side of the negotiating table. Furthermore, women who swear judiciously -- and like it -- generally appear confident.

Although cursing like a sailor is guaranteed to destroy one's femininity rating, it can be an effective strategy for some women. One tough-talking saleswoman uses profanity to drive home the message that she is wooing her buyers -- all men -- not for personal reasons, but for sales. "A lot of sniffing and wagging goes on in business that could be misinterpreted as male/female courtship," says another woman, who has seen the saleswoman in action. "Four-letter functionals neutralize her femininity."

The most acceptable forum for swearing is among teammates working toward a common goal. As the work progresses, and people grow closer, the language often deteriorates. Rather than showing disrespect, a colleague's burst of expletives can indicate trust and acceptance; in effect, it says, "You are one of us, part of the team. We don't have to watch what we say among ourselves."

Because swearing means letting your hair down and becoming closer, however, its use can be touchy, especially between men and women. While some people may claim to be offended by strong language, in many cases it's the familiarity, not the filth, that puts people off. "Swearing can presume a level of friendship that is not formal and professional," says Potash. "Crossing that boundary with someone who is not yet sure she or he trusts you could be a problem."

Swearing rules are about the same for both men and women. Most women agree you can swear with impunity if you own the company or if you work for a company in which it is the norm. (Some, in fact, hold that if your company's style is one of swearing, you should use the language to get ahead.) You can probably swear if your boss does and in situations where you are working closely with peers.

But you can get yourself into a real snafu by not minding your swearing manners. It goes without saying that you should rein in your expletives in the presence of clients. Take care around people who were unnerved by the '60s, or those with newfound religion. And refrain when your listener is using a speakerphone.

It's important to heed the degrees of profanity as well. Hells, damns and deities are so common nowadays that they carry little prohibition or punch. Less acceptable are four-letter words describing bodily functions or sexual matters. Never swear when your are truly angry -- it sounds like a temper tantrum. And don't swear at someone -- the recipient will never forget. The verbal aggression will show you are out of control, a far more damning business behavior than swearing.

And above all, don't apologize for swearing. It sometimes serves a hell of a good purpose.