Instant Mess Grab the spackle. Instant messaging is the latest crack in your security.

Rapid growth in instant messaging is causing equally rapid growth in risk for any business with employees who use it. Theft of confidential information, infection by computer viruses, invasion by hackers and potentially devastating lawsuits are just a few of the risks cited by experts on the dangers of workplace proliferation of IM, as it's popularly known.

"Sexual harassment, defamation, discrimination, lost productivity--the list goes on and on," says Nancy Flynn, executive director of the ePolicy Institute, a Columbus, Ohio, organization that sells advice on electronic communications. Flynn says risks from instant messaging parallel those posed by e-mail, and a 2001 survey by her organization found 8 percent of firms had faced claims of sexual harassment or discrimination resulting from e-mail or Internet use.

Use of IM at work doubled last year, according to figures from research firm Jupitermedia. ComScore Media Metrix Inc., another technology-trend-tracking firm, says more than 17 million Americans used IM at work in June 2002, up from less than 14 million in November 2001. Other analysts say that by the end of next year, IM will be used at work by someone in nearly every U.S. company.