Mills stands to profit from a large chunk of McCartney's estimated 1.5bn fortune.

With such a sizeable bank balance, both parties had their pick of lawyers and opted for Britain's leading counsel. Anthony Julius and Fiona Shackleton represented Prince Charles and Princess Diana and are believed to charge in the region of 1,100 an hour.

Unfortunately, few people can afford celebrity lawyers and the rising numbers of couples in Ireland seeking a divorce are often crippled by the high costs.

According to CSO figures released last month, 4,126 divorces were granted in Ireland in 2005 compared to 3,914 the previous year.

The more complex the divorce, the bigger the final fee will be as solicitors spend more billable hours resolving the couple's issues. Costs spiral when there is a substantial disagreement or complicated financial matters. Couples will often spend up to 25,000 battling it out in court.

However, there are ways of reducing costs. According to David Bergin, principle of O'Connor and Bergin Solicitors, although pre-nuptial agreements are not legally binding in Ireland, within the next year judges will begin taking them into account.

"A committee has been appointed by justice minister Michael McDowell to look at the issues of pre-nuptial agreements over the coming months and this will encourage judges to give them a second look, " said Bergin.

Pre-nuptial agreements are not recognised by Irish courts and since the introduction of divorce in 1997, a number of Irish men have found themselves grudgingly handing over an ample slice of their assets when the marriage breaks down.

"If pre-nuptials were legalised it would significantly reduce the costs of divorce as couples would not have to go into court to fight about who gets what, " said Bergin.

Muriel Walls, partner at McCann Fitzgerald, agrees:

"If people want to sort out their affairs they should be facilitated. It allows for a more orderly exit. We have witnessed a rising number of clients requesting them.

They are particularly beneficial in the event of second marriages where children already exist."

Another low-cost route is mediation. This is a process that enables both parties to negotiate their own agreement. The state-funded Family Mediation Service is free to all, regardless of income.

After a successful mediation, couples are given a deed of separation which can be made legally enforceable with the aid of a solicitor.

According to Bergin, mediation is most helpful with regard to child custody issues which can often lead to raw emotions.

"It can be a huge help and significantly lower fees. However, couples attempting to resolve the division of assets should employ the services of a solicitor from the outset."

In response to the rising numbers of couples seeking divorces, a handful of businesses are now offering a DIY divorce solution for about 600. In 1997, Cathy O'Brien could not afford the legal bills associated with hiring a solicitor so she filed the papers herself for 20. Following the successful low-cost outcome she began helping out other people with their divorce papers and she now runs DIY Divorce.

Couples living apart for more than four years who both live in the Republic can use her service. The company does all of the paperwork and the service costs between 550 and 650 for consenting and non-consenting divorces.

The fee can be paid in stages.

The process takes about three months, although couples in Dublin are often dealt with more quickly as divorce cases are held every week in the capital.

"We launched the business in 2000 and this year we dealt with about 1,000 clients. Most of them cannot afford the traditional solicitor route. We often get referrals from solicitors and court offices."

According to O'Brien, the two main benefits are the low cost and speed of the process.

Walls believes that the DIY divorce route can be a good low-cost alternative if all financial matters are already resolved. However, she warns that couples are not always aware of emerging complications until they sit down with a solicitor and receive professional advice.

"Sometimes people don't realise the financial implications of a divorce. For example, they will no longer be entitled to pension or inheritance benefits."

Bergin agrees that couples should tread with caution. "I am currently dealing with four cases where people paid for a DIY divorce but the pension was overlooked. It's very difficult to sort this out after a couple have been divorced.

There's no redress. Couples sometimes think their divorce is uncontested but dig a bit deeper and you'll find that's not the case."

An important factor to consider when choosing what route to take . . . the DIY road or the traditional solicitor . . . is that paying for professional legal advice will often net you a good return. Couples contemplating divorce would do well to remember that a good solicitor will see you through one of the most traumatic events you will ever face.

According to a family law solicitor from Dublin, her job lasts 24 hours a day, a task that she does not shirk.

"It's so important to remember the human element when dealing with a divorce case. These people are wounded and upset and need to employ somebody who can carry them through the whole process. People need your support far more in family than a normal litigation case. This is not an eighthour a day job, it's 24 hours a day. You are vulnerable when you love someone and it takes a long time to work through that. If you only thought of the legal aspect, you wouldn't be a family law solicitor."