Philippine crowds forced a president out of office earlier this year

TI points to the movement towards a labelling system to cut down on the number of "conflict diamonds" from places like Sierra Leone and Angola making their way unheeded onto the market.

The OECD's Anti-Bribery Convention has helped, TI says, although some countries - notably the UK - have yet to bring its stipulations into domestic law.

And civil society in some countries is gaining strength.

Stumbling blocks

But much more work is needed, the report says, particularly in areas such as party funding, institutional development and government procurement.

In Germany, the scandals of the past two years involving the Christian Democrat Party - in power throughout most of the 1980s and 1990s - demonstrate the insidious tendency of political parties to fund themselves through favour-broking and kickbacks.

Thaksin: Denied bribing judges to escape corruption probe

Thailand's prime minister, Thaksin Shinawatra, only narrowly avoided a court probe into alleged corruption and vote-buying.

And in the US, the whirlwind - if ultimately unsuccessful - presidential campaign of Senator John McCain was largely built on opposition to what many Americans see as graft by much of the political class.

Worse, where anti-corruption efforts are instituted, they can be undermined either through insufficient independence or by being used to settle political scores.

It is only in the past few weeks that South African anti-corruption investigators have been able to penetrate ruling party opposition and question senior government figures about a huge alleged arms procurement scandal.

Procurement is a universal problem, TI points out, and similar cases can be found across the world.

Kenya's anti-corruption force was declared unconstitutional by the Supreme Court.

And in Vietnam, most accusations of corruption have come from the prime minister, and most of the accused are his political opponents.

Private sector responsibility

Businesses, too, need to do more, TI says, quoting its own "Bribe Payers' Index" which shows that numerous multinational firms are still happy to bribe foreign officials to get what they want.

And the wholesale liberalisation and privatisation required of developing countries as a condition for receiving aid has often exacerbated the problem.

Without proper oversight, privatisations have too often been decided on the basis of whose sweeteners are best, not who provides the best deal for the country and its population.