What is the most difficult situation you have ever faced and how did you tackle it? The interviewer is really trying to find out what your definition of difficult is and whether you can show a logical and calm approach to problem solving.
This can be a trap! To avoid it, select a difficult work situation which was not caused by you and which can be quickly explained in a few sentences. Explain how you defined the problem, what the options were, why you selected the one you did and what the outcome was. Always end on a positive note and explain what you learnt from the situation.
What do you like about your present job? The interviewer is really attempting to find out whether you will enjoy the things the job has to offer.
This is a straightforward question. All you have to do is make sure that your likes correspond to the skills required in the job on offer. Be positive: describe your job as interesting and diverse but do not overdo it - after all, you're leaving!
Tell me what you dislike about your present job? The interviewer is trying to find out whether the job on offer has responsibilities you will dislike or which will make you unsuitable.
Be careful with this one! Do not be too specific as you may draw attention to weaknesses which will leave you open to further problems. One approach is to choose a characteristic of your present company such as its size, its slow decision- making process and so on. Give your answer with the air of someone who takes problems and frustrations in your stride as part of the job.


How would you define your greatest weakness? The interviewer is asking about your self-perception and awareness.
You have two options - use a professed weakness such as lack of experience (not ability) on your part in an area that is not vital for the job. The second option is to describe a professional or personal weakness that could also be considered a strength and the steps you have taken to combat it. An example: "I know my team think I'm too demanding at times - I tend to drive them pretty hard - but I'm getting much better at using the carrot and not the stick." Do not use a personal weakness such as " I'm not a morning person - I get much better as the day goes on." Always end on a positive note. It might be useful to comment on what you have learnt from the experience.
What is the most difficult decision you have made? The interviewer is saying "I need someone who is strong and decisive but who has a human side."
Your answer must not display weakness. Try to focus on decisions that have to be made without sufficient information. This will show your positive side. For example "I like to make decisions based on sufficient information and having alternatives. When you have to make quick decisions, you have to rely on gut feeling and experience."
Why do you want to leave your current employer? The interviewer is trying to understand and evaluate your motives for leaving.
This should be straightforward. State how you are looking for more challenge, responsibility, experience and a change of environment. NEVER be negative in your reasons for leaving, and it will rarely be appropriate to cite salary as the primary motivator.