The word on the street is that everyone is talking about tax amnesties.

In the professional sector, especially among tax advisers, there is a sense that Revenue & Customs may be about to consider one here.

The idea is one that has perhaps reached its moment in the UK. Various other jurisdictions have tried their hand at amnesties with greater or lesser degrees of success. The objectives of these exercises have varied from case to case. Inevitably, however, they are designed to bring in greater tax revenues, encourage national taxpayers to repatriate offshore funds and to remain on the straight and true path in the future.

Francesca Lagerberg, chairman of the ICAEW Tax Faculty and Grant Thornton's national tax office head, says: 'The effectiveness of these amnesties depends on what they were designed to achieve. It is arguable that the German and Italian amnesties were not hugely successful in terms of the amount of tax revenue they brought in. But as a warning to taxpayers whose assets were offshore, it was perhaps another story.'

Lagerberg says that the most successful amnesty was in Ireland. 'The Irish amnesty was conducted in 2004. It targeted 14,000 taxpayers. The average tax yield each year in Ireland is EUR42bn (£28bn). In the 2004 amnesty, the Revenue Commissioners received EUR838m (£553m). That is not too bad as a percentage and is significantly higher than the income from other amnesties.'

The Irish have followed up this exercise with a name and shame list, on which defaulters are identified with the amounts of back tax owing.

This has proved uncomfortable for many leading Irish citizens, including politicians, business people and established entertainers.

Lagerberg says the Irish amnesty was, in practice, partial. Unlike others, where the entire outstanding sum was written off, the Irish gave amnesty for a reduction in the penalty for failing to pay.

So, in this model, the Irish paid their back taxes and their interest.

Normally, the penalty for late payment is 100% of the outstanding balance.

Under the terms of the amnesty, defaulters who signed up and paid their back taxes and the interest owing were let off 90% of the penalty.

The UK Treasury is short of money, and for the last two years has been talking energetically about the tax take. This is the amount of money that the Treasury anticipates it will draw in from tax revenues. Tax practitioners argue - sometimes - that there is significant disparity between what the Treasury thinks it should receive and the amount it is actually entitled to.

A tax amnesty for UK citizens, who have placed their assets in jurisdictions as widespread as the Isle of Man, the Cayman Islands, the British Virgin Islands and Singapore, could be on the cards. The Revenue has never done one before, but, under the leadership of Paul Gray, it is seeking new solutions.

Tax professionals say that the success of any amnesty would be determined by its targets at the outset. The British tax authority could choose to go for the partial approach adopted by the Irish or determine that it would forego outstanding payments in favour of compliance in the future.

The Treasury could be guided by the story of the European Savings Tax Directive. Here, the established nations of Europe tried to force tax payments from their residents related to interest earned on accounts held from offshore financial centres.

The big powers of Europe - the UK, Germany and France - ultimately forced through the directive with the express hope of bringing in tax on interest payments from expatriated accounts.

The directive was ultimately a victory for politicians, but it failed to generate the desired and predicted substantial payments from offshore accounts to national treasuries.

A similar pattern can be seen with tax amnesties in Germany and Italy.

Both were aimed at national residents who placed their savings in Switzerland.

This is the number-one destination for EU residents' savings. At one point 39% of all such money went to Switzerland. Now it is around 27%, but the Swiss financial sector still remains dominant.

The Italian government ran two amnesties, which were more successful in frightening its citizens than in terms of income derived, but they had the peripheral benefit of annoying the Swiss government. This always plays well among Italian politicians.

There has even been talk of a pan-European amnesty, but realism may well hold that at bay. There are so many conflicting opinions in Europe about the value of a collective amnesty that in all probability one will never see the light of day. There are two prevailing views about tax in Europe.

These are exemplified in the row over the common consolidated tax base (CCTB). The CCTB is the passion of the EU's taxation commissioner Laszlo Kovacs. He is in polar opposition to internal markets commissioner Charlie McCreevy on the proposal.

Kovacs is aiming to present formal proposals for harmonising EU states' corporate tax policies in 2008. McCreevy comes from Ireland, which has some of the lowest corporate tax rates in the EU. He believes that tax competition is preferable to tax consolidation.

Other states believe the CCTB is a non-starter for pragmatic reasons.

But the political debate that follows Kovacs' proposal next year will characterise the huge split at European level about tax policy.

During the last decade, the idea of national tax amnesties has gained credence. The Germans, the Italians, the Spanish, the South Africans and the Irish have all tried their hand at amnesties with varying degrees of success.

Observers argue that success depends on the criteria by which a tax amnesty is judged. If the two amnesties run by the Italian government for its nationals who deposited savings in Switzerland were judged on purely an economic basis - how much tax the Italian tax authority generated - and the funds that were redomiciled back home, they were failures. But viewed from a political perspective they were successful.

South Africa ran a tax amnesty for small business last summer, hoping to bring 100,000 SMEs into the tax system.

Finance minister Trevor Manuel said that businesses with a turnover of up to 10m South African rand (£700,000) qualified for a waiver of taxes and penalties for all assessment years up to March 2005.

But those qualifying would have to pay a levy of no more than 5% on taxable income for the 2005/06 financial year. At the time, he proposed that the amnesty apply to businesses with a turnover of no more than 5m South African rand, while the penalty would have been 10% of the 2005 taxable income.

The minister said that, initially, the amnesty would have been applied in two phases, starting with the tax industry and then the remainder of the small business sector. But these were then integrated into one exercise, which runs until May 2007.

The South Africans have a history of tax amnesties, having run a similar exercise to the German and Italian initiatives in 2003 and 2004. Manuel said at the time that the exercise was more about repatriating capital and securing back taxes. He said that the forex amnesty, as it was dubbed at the time, generated 300 inquiries a day from potential participants.