The weakness question represents the most common and most stressful one posed during interviews. Yet in today's weak job market, the wrong answer weakens your chances of winning employment.

Some people offer replies they mistakenly assume that bosses love, such as 'I am a perfectionist.' That response 'will be used against you' because you appear incapable of delegating, warns Joshua Ehrlich, dean of a master's program in executive coaching sponsored by BeamPines Inc., a New York coaching firm and Middlesex University in London.

A careful game plan could help you cope with the shortcoming query in a way that highlights your fit for a desired position. Job seekers who field the question well demonstrate that they can 'take initiative and improve themselves,' Mr. Morrow says.

The key? Thorough preparation. Career specialists suggest you take stock of your weaknesses, focusing on job-related ones that won't impede your ability to perform your duties. Tony Santora, an executive vice president for Right Management, a major outplacement firm in Philadelphia, says an information-technology manager flubbed a 2007 interview by choosing a personal foible as his reply: 'My true weakness is that I am a terrible cook.'

Rehearse your responses aloud, role play with a friend or videotape yourself -- but don't memorize your words. As you review the video, look for aspects 'you would like to change so you can continue to get better as you practice,' says Peggy Klaus, a leadership coach in Berkeley, Calif.

The IT manager changed his tune after practice sessions with fellow job seekers and a counselor in Cincinnati for Right Management. He instead said he worked such long hours that he found it difficult to stay current with world events. So, he spent 30 minutes every evening catching up at home.

When the manager pursued an opportunity at a global drug maker, his revamped response 'really resonated with the interviewer,' says Mr. Santora. The manufacturer hired the man.

It's equally important that you consider an employer's corporate culture. While being interviewed by a start-up, 'you could say, 'My weakness is I get bored by routine,'' says Ben Dattner, a New York industrial psychologist.

Ideally, your reply also should exclude the word 'weakness' and cover your corrective steps. Dubbing your greatest fault a 'window of opportunity' signals your improvement efforts should benefit the workplace, says Oscar Adler, a retired Maidenform Brands sales executive and author of the book, 'Sell Yourself in Any Interview.' For instance, he suggests, a salesman might note that he sold more after strengthening his facility with numbers.

When an interviewer pops this nerve-wracking query, your body language counts as well. The wrong nonverbal cues undercut your credibility. Certain candidates hunch over, glance furtively around the room or wring their sweaty palms. 'They sort of look like they're being asked a question they can't handle,' says Mr. Adler.

Maintaining eye contact, regular breathing and a broad smile impress employers that 'you're prepared for the weakness question,' says psychotherapist Pat Pearson, author of 'Stop Self-Sabotage!'

For the same reason, you seem thoughtful if you pause before responding. But don't wait too long. 'If you're going to take a minute,' Mr. Morrow cautions, 'I've just identified your weakness.'