Although all the evidence shows that drawing up a will makes good sense, most people in the UK choose not to.

Will making has never been heavily regulated

In England and Wales about two thirds of people die intestate, a fact that Geoffrey Shindler, the Chairman of the Society of Trust and Estate Practitioners, struggles to understand.

"I don't know whether it's inertia or sheer stupidity," said Mr Shindler. "There's no sensible reason for it although a lot of people think that if they make a will then they're going to die."

The business of will making has never been heavily regulated in the UK, said Brian McMillan, of the Society of Will Writers, the self-appointed watchdog in this area of law.

But in 1989 the business was widened when the Lord Chancellor introduced new laws allowing anyone to write wills for profit.

Anyone aged 18 or over can make a will and it must be signed by the testator (the maker of the will) and witnesses.

Divorce automatically alters a will

A will can be revoked in one of several ways such as physical destruction by the testator or making another will, which automatically supersedes the previous document.

In the case of divorce, a will made beforehand is only partially revoked. It remains valid but references to the former spouse are deleted.

It is a surprise to most people that a will can be altered after death by the people mentioned in it. If all the beneficiaries are adults and they reach a consensus then that is enough to alter the will. This is binding even if the testator has specifically asked for the will not to be altered.

Laws are different in Scotland

"If children are involved then the matter must go to a court," said Mr Shindler. "It is then up to a judge to decide if the decision to alter is in the interests of the child."

In Scotland, the law governing wills is substantially different from that in England and Wales, said Edinburgh solicitor Richard Filleul, of the firm Murray Beith Murray.

"There are certain formal differences such as the fact that every page on a Scottish will must be signed, whereas in England it's just the last page. And only one witness is needed, instead of two," said Mr Filleul.

The main difference is that the spouse and children are granted specific rights if they are not accounted for in the will.

"If you cut children out they have a right to claim half of all moveable [not property] assets if there is no surviving spouse; or a third if there is a spouse," said Mr Filleul.

Similar rights are accorded to a spouse who has been cut out of the will.