Guess who's looking at your Web page: college-admissions officials and employers are starting to check out candidates on Web sites like Facebook and MySpace.

One recent university graduate may still be wondering why she didn't get a job offer from Green Ivy Educational Consulting, which teaches organizational skills to high school students in the San Francisco area. Ana Homayoun, who runs the company, thought the young woman was a promising candidate--until she looked her up on Facebook, the popular social-networking site. There, Homayoun found commentary about the student's drinking and smoking habits, including testimonials from friends, and pictures.

"I was just shocked by the amount of stuff that she was willing to publicly display," says Homayoun. "When I saw that, I thought, 'OK, so much for that.'"

Many companies have been using search engines like Google and Yahoo to conduct background checks on jobseeking college seniors for some time. But now, college career counselors and other experts say, recruiters are starting to look up applicants on sites like Facebook, MySpace, Xanga, and Friendster, where high school and college students often post provocative photographs and text in what some mistakenly believe is relative privacy.

When viewed by corporate recruiters or admissions officials at colleges and graduate schools, such pages can make students look immature and unprofessional, at best.

"It's a growing phenomenon," says Michael Sciola, director of the career resource center at Wesleyan University in Middletown, Conn. "There are lots of employers that Google. Now, they've taken the next step."

At New York University, recruiters from about 30 companies told career counselors that they were looking at the sites, says Trudy G. Steinfeld, executive director of the school's career development center.

"The term they've used over and over is 'red flags,'" Steinfeld says. "Is there something about their lifestyle that we might find questionable or that we might find goes against the core values of our corporation?"

HOW PRIVATE?

Facebook and MySpace are only two years old, but they've attracted millions of avid participants who mingle online by sharing personal information, often intended to show how funny, cool, or outrageous they are. Concerns have already been raised about these and other Internet sites, including their potential misuse by stalkers and students exposing their own misbehavior.

On MySpace and similar sites, personal pages are generally available to anyone who registers, with few restrictions on who can join. To register on Facebook, high school students must have a school e-mail address or be invited to join by another student at their school; college students must have a college e-mail address. Personal pages on Facebook are restricted to friends and others on the user's campus, leading many students to assume that they are relatively private.

But companies can gain access to the information in several ways. For example, they sometimes ask college students working as interns to perform online background checks, says Patricia Rose, the director of career services at the University of Pennsylvania.

Rose says a recruiter rejected an applicant after searching the name of the student, a chemical-engineering major, on Google. Among the things the recruiter found was this remark: "I like to blow things up."

Some companies, including Enterprise Rent-a-Car, Ernst & Young, and Osram Sylvania, say they do not use the Internet to check on college job applicants.

"I'd rather not see that part of them," says Manreen Crawford Hentz, manager of talent acquisition at Osram Sylvania, a lighting manufacturer. "I don't think it's related to their bona fide occupational qualifications."

But other companies, particularly those involved in the digital world, say researching students through social-networking sites is now fairly typical.

"For the first time ever, you suddenly have very public information about almost any candidate," says Warren Ashton, group marketing manager at Microsoft.

Applicants may not know when they have been passed up for an interview or a job offer because of something a recruiter saw on the Internet. But more than a dozen college career counselors say recruiters have been telling them since last fall about incidents in which students' online writing or photographs raised serious questions about their judgment, eliminating them as job candidates.

SMARTER POSTING

Some college career advisers are skeptical that many employers actually check applicants online.

"My observation is that it's more fiction than fact," says Tom Devlin, director of the career center at the University of California, Berkeley. At a conference last May, Devlin says, he asked 40 employers if they researched students online and every one said no.

Nevertheless, many career counselors are urging students to review their pages on Facebook and other sites, and to remove inappropriate photographs or text.

Melanie Deitch, director of marketing at Facebook, says students should take advantage of the site's privacy settings and be smart about what they post. But they may not be following this advice.

"I think students have the view that Facebook is their space and that the adult world doesn't know about it," says Mark W. Smith, assistant vice chancellor at Washington University in St. Louis. "But the adult world is starting to come in."

Alan Finder covers education for The New York Times.