She was a young TV reporter who'd finally landed a job interview with a big-city station. She arrived on time, shook hands firmly and remembered to make eye contact. Her answers to 45 minutes of questioning were confident. The interview seemed to progress nicely -- until the end, when the interviewers said, "We're not really sure you're suitable for the job."

Outraged, she shot up from her chair and muttered, "Well I'm not sure I want it." Grabbing her coat, she marched out in a huff.

The rejection letter came a few days later -- after she had heard the station tested all applicants with that line.

"How you leave often determines whether you get the job or not," says Martin Yate, training director for Dunhill Personnel Systems, a national job placement firm. Yate, whose book Knock 'Em Dead (Bob Adams Inc., $5.95) catalogues tough interview questions and how best to answer them, says the last minute or two can be the most critical part of a job interview -- especially when all has gone well beforehand.

"The last image I leave in your mind is how I leave you," says Yate, who trains people on both sides of the interview desk. "Too many people think that having an interview is tantamount to getting an offer. But this is a trial. A performance. All the world's a stage, and how you leave it determines whether you get a curtain call and a standing ovation -- or nothing."

Too often, he adds, even people who've mastered interview skills neglect the finale: "Until you are shown out the door, you are on show. But instead of finishing with a bang, many of us finish with a whimper. The best image I can possibly leave you with is a positive and powerful one -- not one of uncertainty, clumsiness or inability to handle pressure."

The traditional signal that an interview is coming to a close is when you're asked if you have any final questions. Then, says Yate, is when to keep in mind the do's and don'ts of making a graceful exit:

Don't discuss salary, vacation or benefits. Although they are valid questions at the right time, if they haven't come up before the end, wait until you get an offer. "The exit isn't the time to ask what the company can do for you," says Yate. "It's when you tell the company what you can do for it." And besides, until you have an offer, you can't negotiate the details.

*Don't press for an early decision. The old I-have-other-opportunities-so-I-need-to-know gambit "annoys the interviewer who, at this point, may have no idea if he wants you or not," says Yate. "It's better to ask, 'When will I know of your decision?' adding, 'I'm very interested in meeting with you again.' "

*Don't show discouragement. Job offers rarely come at the end of the interview. "The image you want to leave," advises Yate, "is self-esteem, determination, enthusiasm, guts and openness."

*Don't ask for an evaluation of your interview performance. Asking "So, how'd I do?" only forces the issue, putting the interviewer in an awkward position.

*Review your personal and professional strengths if they haven't been addressed and are relative to the job.

*Recap how you can benefit the company. Review the job requirements and match them to your strengths. For example, say, "As I understand it, Mr. Jones, you're looking for someone who can do A, B, C and D. I can do A, B, C and D. Now what should I do next to get this job?"

*Show decisiveness. If offered the job, don't hem and haw. Accept it with enthusiasm. Be in control: You can always change your mind later.

*Be certain to get the correct names and spelling of names of anyone who interviewed you.

*Find out if this is the only interview. If it is, advises Yate, say, "I'm enthusiastic about the job and the contributions I can make. What can I do between now and when you make the decision to assure I get the job?" If there will be other interviews, ask in a forthright manner, "Is now a good time to schedule our next meeting?"

*Depart in the same polite, comfortable and assured manner with which you arrived. "Look the interviewer in the eyes, smile and give a firm handshake," says Yate. "Say, 'This has been an exciting meeting. It's a job I can do and I can contribute to your goals. When will we speak again?'

"Closing an interview is a technique," adds Yate. "Sometimes, the best bits of a story come when you put your pen down. People are off their guard at the end. People relax. But this is the time to be alert." The Hidden Job Market

Interview skills are just part of the job search techniques taught at Senior Employment Resources' monthly Job Club in Annandale. Other topics scheduled for the next two-day meeting, Dec. 10 and 11: finding the hidden job market, developing a personal network and tailoring your re'sume'. The club is available to residents, 55 and over, of Fairfax, Loudoun and Prince William counties, and Falls Church and Fairfax City. No fees. (703) 750-1936. Political Positioning

Registration has started for George Washington University's Washington Representative Program. These graduate-level courses cover how to monitor legislation, target information sources, develop grassroots support and organize political action committees. "Lobbying at the State and Local Level" meets for four Wednesdays beginning Jan. 8. Tuition: $135. (202) 676-7216.