Advisers and recruiters say that students who accept job offers should renege only if circumstances arise beyond their control.

A student's acceptance represents a commitment to the job and the company. When a student reneges, the company loses time and money. Company recruiters must launch another job search, and filling the position can take months.

"A candidate should never renege on an offer unless something has come up that makes it impossible for a person to accept it," said Dr. James Burke, who retired last year as manager of technical recruiting and university relations for Rohm & Haas. "Certainly they shouldn't (renege) cavalierly. It should be only under extreme circumstances."

Burke, a member of the American Chemical Society's board of directors, said those circumstances might include an obligation at home, such as caring for ailing parents or remaining with a spouse who was transferred elsewhere or no longer can leave the area.

Dr. Ron Webb, manager of doctoral recruiting and university relations at Procter & Gamble in Cincinnati, said situations in which student renege are rare, perhaps occurring once in hundreds of cases.

"We would certainly encourage people to not do so unless it was absolutely necessary," Webb said. "When those situations do come about, we are open to discussion and understand that from time to time people do have to change their minds."

In one recent situation, Webb said, the health of a candidate's parents suddenly prohibited the candidate from relocating. "It was an unexpected situation and it was serious, but we listened, and we understood," he said.

A student also could justifiably renege if an employer provided inaccurate information about the company or position, said Dr. Leigh Turner, executive director of the Career Center at Texas A&M University.

Even then, Turner recommends that students consult their school adviser or career services counselor before reaching a decision. "We prefer that the student let us assist them so we can contact the employer and perhaps resolve the situation to everyone's satisfaction," Turner said.

Turner co-authored a paper on rescinded employment offers for the National Association of Colleges and Employers' (NACE) committee on principles for professional conduct. The paper says rescinding an offer or an acceptance should occur only when no realistic alternative exists.

Turner said students who have seen financially strapped companies rescind offers to friends or family members may be less trusting when they receive an offer themselves.

But students still need to consider their decisions carefully, she said, adding that employers should give students at least two weeks to decide, and students should stop interviewing once they accept a position.

No matter how tempting, a more attractive or lucrative job offer does not justify reneging on an acceptance, Burke said.

"To renege on an offer simply because another offer came in later and looks a little better is wrong," said Burke, who co-authored the NACE paper.

For example, a student might accept an offer from Company A and turn down Company B, where the student also interviewed. But what if Company B then offers an additional $10,000?

"That would be tempting because it's certainly the best cash offer," Burke said. "But there's a thing called principle."

Procter & Gamble's Webb said students should resolve other job possibilities before accepting a position, especially if they're interested in another job.

"Let's say you've got a person who interviewed with company A and B," Webb said. Company A makes an offer and gives the student some time, maybe two to four weeks, to reach a decision. During that time, the student can contact Company B and say, "I've got an offer. This is the deadline. Where am I with you?" The student can then make a decision within Company A's time frame.

Although a student who reneges won't face legal challenges, the decision can harm an employer and damage the student's reputation.

Burke noted, "Suppose you invite five very good candidates to interview and then offer the job to one, who accepts.

"You would then inform all the other candidates that another candidate had accepted the position. When the candidate later reneges, your other candidates most likely have accepted other jobs. "You might have spent $5,000 apiece on each of the candidates in terms of travel and employees' time," Burke said. "Those are unrecoverable costs, and now you have to start over because the candidate who had accepted has backed out."

Webb said that when a candidate accepts a position, P&G pulls its ads from its Web site and job boards and ceases its interviews. If a candidate rescinds an acceptance, "we've got to start putting ads in journals and on job boards, reinitiate the interviewing process, and this takes time," he said. "All of the sudden, we're six months behind the curve."

Meanwhile, the company must struggle to complete work because a position that hiring managers expected to fill remains open.

Some experts believe students who renege reflect poorly on their school.

"Most students probably don't realize what an embarrassment it is for their department and university when they renege on offers," Burke said.

An associate of Burke's at a prominent university told him how seriously the department there treats reneging offers. In one instance, a company complained to the department after a student reneged.

"The department was horrified," Burke said. The department chair, the student's adviser, and a few other faculty members brought the student into the chair's office and "basically blistered him for showing up the department. Then they went back and apologized to the company that one of their students would do such a thing. So believe me, it is taken very seriously."

But Webb said he would not blame a university or department for a student's decision because the student's behavior reflects on the individual, not the school.

If a student needs to renege, experts recommend informing university advisers and talking by phone with the company official who extended the offer.

"You certainly wouldn't want (to leave) a very terse but brief e-mail message, such as, 'I can't come,' period," Webb said, but deal with the situation professionally and talk to the people affected by the decision.

Students need to explain why they're going to rescind, said NACE general counsel Rochelle Kaplan. At times, honest communication can resolve a potential problem or concern.

"It gives the employer an opportunity to mollify the student's fears," Kaplan said. "The student might be reading in the newspaper all kinds of horrible things happening to the company, and the student might get scared that he or she will come to work and get fired the next day. That might not be the case. The employer should have an opportunity to explain."

In other cases, a student who must move elsewhere with a spouse or delay acceptance because of a family situation may discover that the company is willing to accommodate them.

"They should contact the company and say, 'Conditions have really changed on my end,'" Texas A&M's Turner said. "The company may say, 'We have another location here,' or 'Don't worry about it; come to work for us in six months.'"

Rachel Smolkin is a Washington-area freelance writer. She previously worked as a national reporter in the Washington, D.C. bureau of the Pittsburgh Post-Gazette and Toledo Blade and covered issues such as health care and education. She also worked at Scripps Howard News Service as a national education reporter and as the Washington, D.C. correspondent for The Albuquerque Tribune in New Mexico and the Birmingham Post-Herald in Alabama.