Bear in mind that the interviewer may be just as nervous as you: they want to select the best person for the job. If he gets it right, the company prospers; if he gets it wrong the company will suffer. Your objective is to impress the interviewer by projecting a professional image and demonstrating your suitability for the job.

Greet the interviewer with a smile and a firm handshake and wait until you are offered a chair before sitting. Be aware of your body language: sit up straight, maintain eye contact and avoid fidgeting or twiddling your thumbs. According to research, the interviewer will decide within just four to nine minutes whether to consider you seriously for the job. So making a good first impression is vital.

Show a real interest in the job. Speak clearly and confidently and make sure that everything you say is factual and sincere. During the interview, bear the following guidelines in mind: Concentrate and listen very carefully to the questions. If you are not sure exactly what is being asked, don't say "Could you repeat the question?" This could make the interviewer feel that you haven't been paying attention. Rather, rephrase the key words and ask the interviewer to clarify: "Do you mean..."

Avoid answering with a simple yes or no. Support your answer with relevant information from your experience and relate everything you say to the job you are applying for.

Do not speak negatively of other people or companies. It makes you look unprofessional. Stay calm. Maintain a positive attitude throughout the interview, speak with energy and enthusiasm, and feel free to pause when you are thinking of appropriate replies. Keep your answers relevant and to the point. A good interviewer will do more than just establish your competence: he will explore your compatibility with the company - your attitudes, beliefs, personality, response to pressure and so on.

To this end, he may ask you deliberately provocative or difficult questions. "Why haven't you found a new position before now?" "What do you think of your boss?" "Don't you think you're a bit overqualified for this role?" "Why should I employ you when I could fill this vacancy from within the company." "What was your biggest mistake or error of judgement?"

Ideally, you'll have anticipated and prepared for difficult questions relating to your experience and capabilities. If you are asked an unexpected question, pause and think before giving an answer and always offer a positive response that relates back to the position you are applying for. For example, "Am I over-qualified? I don't think so. Strong companies need strong people, and I believe that a growing and energetic company like yours will make the best possible use of my skills and experience. That's why I applied for this job."

Usually the interviewer will ask you if you have any questions. The worst response is "Can you tell me a little more about the job?" Be specific and ask questions that have not already been answered in the job description. For instance:

What would my initial assignments here be? What are the greatest challenges of this role? I understand that the company is about to enter the health care market. Will that development have any impact on my role? At the very least, ask the interviewer when he will be making a final decision and whether he needs any further clarification about your experience.

Leaving the interview...

Don't let your guard down yet. You want the interviewer to remember you positively, so thank them for their time and consideration and tell them how much you enjoyed discussing the job with them.

It's important to convey that you really are interested in working for the company, because - all other things being equal - the job is likely to go to the more interested candidate. For example, you could say: "Mr Jones, I find this opportunity very interesting. Your company is clearly doing exciting things and I believe that with my background and experience I could make a significant contribution to your team."

Tell the interviewer that you look forward to seeing him again, shake his hand and leave.

Dress is one of the most important ways of getting people to take you seriously. Clothes have a language, and what they say about you will have a direct impact on your success at interviews - and beyond.

That means managing the impression you make. It means projecting a professional image. It means using the vocabulary of clothes and accessories to give yourself the best chance of achieving your goals.

In short, you must look the part!

Of course, looking the part will vary enormously depending on the company you're applying to, its business, its product or service, its traditions and so on. The point is to dress in a way that is appropriate to the particular organisation. What you wear for an interview at a bank may differ from what you wear for a job at an advertising agency. But be careful. An advertising agency's finance department may have a more formal dress code than its creative department.

For the purposes of an interview, it's best to err on the side of formality unless your Adecco consultant or the recruiting company indicate otherwise. You are expected to dress well and your objective is to project an image that communicates professionalism, competence and presence. Here are a few guidelines:

Choose the best quality clothes you can afford. One good suit in navy or grey worn with a white or light blue shirt is a good start (although women can interpret this more freely than men.) Men should wear dark socks and well-polished shoes. Women should usually wear shoes with a closed toe and heel. Aim for clean lines with a minimum of decoration, restricting splashes of colour to your tie, scarf or blouse. If you wear jewellery, make sure that it is understated and discreet. Perfume and aftershave should be used in small amounts, if at all. Details matter. Hands, hairstyle and make-up should be simple and meticulous, and good personal hygiene - including clean nails and fresh breath - is vital. Remove any outer garments in the reception area.