Here are a few things to keep in mind when going on a job interview: Don't get drunk during the meeting. Wear something more professional than jeans and flip-flops. Keep your conversation free from curse words. Know what the company does. Don't invite your parents to join you on the interview.

While these things may seem obvious, a substantial chunk of job seekers violate those rules and oh, so many more.

David Hoffman recalls taking a candidate out for dinner for the final interview. The candidate impressed the hiring committee throughout several rounds of interviews and he was their choice to become a senior consultant at DHR, the Chicago-based executive search firm of which Hoffman is CEO. This informal meeting was the final hurdle.

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The candidate drank so much scotch that Hoffman had to call an ambulance and the candidate was taken by stretcher to the hospital where he was treated for alcohol poisoning. "You think I'm embellishing but I'm not," says Hoffman.

They gave the candidate access to alcohol on purpose. Since many senior level positions at DHR require entertaining clients, Hoffman intentionally take candidates on a dinner interview to see if they drink too much. The candidate called the next day to apologize but by that point Hoffman and his staff decided he wasn't someone they trusted to have on their team.

Interviewees: Never forget your judgment is scrutinized at every point of the interview process. That means everything--from what you wear to the language you use--will be examined. Hoffman offers another example in which he flew to Nashville, Tenn., to conduct a preliminary interview on a candidate for president of a waste management firm in Chicago before the client met him.

When he reached the baggage claim there was a casually dressed man in jeans and a T-shirt with a box of cigarettes rolled up in his sleeve waiting for Hoffman. He recalls thinking, That's so classy that the candidate sent a driver to pick me up. That person turned out to be the actual job candidate.

When Hoffman suggested there might be a miscommunication about the job and its senior level, the candidate told him, "I'm a hands-on manager, I thought this dress was appropriate."

"That was the end of the interview," says Hoffman. "I got on the next flight out of Nashville."

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Some might think that's harsh, but consider this: If a candidate for a high-level position can't determine the appropriate dress, how are they to be trusted managing an organization?

That's precisely what executives at Campbell Soup Co. felt when they recently rejected a candidate who asked to be excused an hour and a half into a job interview so she could check on her 12-year-old son who was waiting for her in the car.

"It showed a lack of judgment," says David Massey, director of global talent acquisition at Campbell. "Had she said, 'My babysitting plans fell through--can we reschedule?,' we would have said 'Of course.' " Or, "You can use our on-site daycare center."

One of the most popular reasons for a quick rejection is cursing. "The F-bomb gets dropped regularly when I ask candidates about their former supervisors," says Campbell's Massey.

Meghan Lantier, an account supervisor at the public relations firm Bliss, Gouverneur and Associates, sympathizes with Massey. When she interviewed a recent graduate of an Ivy League university for an entry-level position two years ago, she asked a typical question: Tell me what it was like working at your most recent internship.

"He started talking about a former boss and said, 'That fu**ing guy I was working with � ' "My mouth dropped open and I couldn't believe this was happening. It was like an episode out of The Office."

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