|Police taking bribes was highlighted as a major problem by the report|
The world is considered a more corrupt place now than it was three years ago, a poll suggests.
Some 56% of people interviewed by Transparency International said their country had become more corrupt.
The organisation put Afghanistan, Nigeria, Iraq and India in the most corrupt category, followed by China, Russia and much of the Middle East.
Meanwhile, a BBC poll suggests that corruption is the world's most talked about problem.
About one in five of those polled by the BBC said they had discussed issues relating to corruption with others in the last month, making it the most talked about concern ahead of climate change, poverty, unemployment and rising food and energy costs.
In the Transparency International survey, political parties were regarded as the most corrupt institutions, and 50% of people believed their government was ineffective at tackling the problem.
One in four of those polled said they had paid a bribe in the past year - the police being the most common recipient.
Some 29% of bribes went to the police, 20% to registry and permit officials, and 14% to members of the judiciary.
Political parties have long been regarded as the most corrupt institutions - they topped the list in Transparency's 2004 barometer with 71%. In this year's report, 80% regarded them as corrupt.
Religious bodies experienced a sharp rise in people regarding them as corrupt - 28% in 2004 increased to 53% by 2010.
People from Afghanistan, Nigeria, Iraq and India were among those who perceived the highest levels of corruption in their daily lives.
At least half of the people surveyed in those countries reported paying a bribe in the past year.
While people from Cambodia (84%) and Liberia (89%) were the most likely to have to pay a bribe, the Danish reported 0% bribery.
Robin Hodess, Transparency's policy and research director, expressed particular concern at the figures on bribery.
"Unfortunately people's experience with bribery most often involves the police, and this is really worrying," she said.
"It's a figure that's grown in the past few years. It's nearly doubled, in fact, since 2006. Nearly one in three people who had contact with the police around the world had to pay a bribe."
By region, people in sub-Saharan Africa were the most likely to have paid a bribe (56%).
Bribe taking was least common in EU countries and North America (both 5%) - although these were the two regions seeing the biggest increase in concern about corruption.
Analysts blame this rising concern on the global financial crisis for undermining people's faith in government, banks and economic institutions.
The lobby group interviewed 90,000 people in 86 countries to compile its corruption barometer.Poverty
The opinion poll commissioned by the BBC sampled 13,000 people in 26 nations.
One question asked people to rate which issues they saw as most serious.
Corruption was ranked as the second most important topic behind poverty.
Respondents in Brazil, Egypt, Colombia, the Philippines and Kenya were especially likely to view corruption as a very serious issue.
In Europe, Italians were the most concerned about bribe taking.
Publication of the BBC poll coincides with anti-corruption day held by the United Nations.