First, I believe passionately in democracy and the rule of law. England has benefited from the most stable national constitution of any country in Europe. That is because the United Kingdom does not have a written constitution. Ours is based on the separation of power between law-makers (Parliament) the executive (Government) and the judiciary. This is all held together by the monarchy, with the Queen as Head of State. This has given us flexibility to respond to change which is much harder in countries with a written constitution and a codified legal system. My first duty is to uphold the constitution and the supremacy of Parliament. So in my daily life, my duty to Parliament must come first. I was elected in Salisbury and sent to London to use my judgement and cast my vote in the interests of my constituents - just as Salisbury's first MPs were summoned to London in 1264 by King Henry III.

In Parliament I listen, debate, vote, ask questions, serve on legislative and scrutiny committees - creating new laws and holding the Government to account. It is Parliament that sanctions government taxation and spending - "no taxation without representation".

For HMG to get its way, it must persuade enough MPs to support it. This is achieved by the Political Party System. I joined the Conservative Party in 1974 out of conviction that it has the soundest political philosophy and that I identify with its objectives and aspirations. In 1982 I was selected to stand in the 1983 General Election (there were 256 people after the job!). So I owe allegiance to the Conservative Parliamentary Party and to the members of the Salisbury Conservative Association. I take the Tory Whip so I accept the collective responsibility for the decisions of my Party leadership.

But I also promised to serve all my constituents, whichever Party they voted for. That is why people of all shades of political allegiance come to me for advice, or to remedy wrongs.

Sometimes I have to fight hard for constituency issues which may not coincide with my Party's policy. Usually these can be resolved amicably - only occasionally have I been unable to support my Party in parliament.

There are other tensions, too. My wife and family must have due priority - and we have a right to a private life. We cannot attend every constituency function - but I do average 5 engagements per weekend. Thank goodness Salisbury is my home town!

Finally, I must have time to myself. I have to live with my conscience and beliefs, with moral and ethical judgements no-one can make for me. I have to be prepared to disagree with vociferous groups and individuals on great and passionate issues.

So, what does a working week look like? Usually I'm in London Monday to Thursday, and in Salisbury Friday to Sunday. Besides attending debates in the Chamber and voting, I may work on committees of the House, back-bench committees, meetings with constituents, local authorities and other MPs, briefings, interviews with the press, radio and TV, phone calls, work on the internet - and a postbag of 50 letters a day. I spend many hours a week writing - articles, memos, references - and just as many reading.