Transparency International, which fights worldwide corruption, says Switzerland is the export nation most effective at preventing bribery in its companies.
But despite achieving the top ranking in the organisation's Bribe Payers Index, Switzerland's score of 7.81 out of ten leaves much room for improvement, says the organisation.
Transparency ranked 30 countries according to their effectiveness in preventing their companies from bribing when doing business abroad.
The head of the organisation's Swiss branch, Anne Schwöbel, said she welcomed the first place for Switzerland but explained it did not represent the whole story.
"The BPI has a score of ten, which indicates a perception of no corruption while zero means corruption is seen as high," she told swissinfo.
"Switzerland's score is 7.81 and this is in our view far from perfect. Seven point eight one does not mean there's a perception of no corruption... I think this is a clear message that we have to improve."
Schwöbel said it was a positive sign that Switzerland had ratified the Organisation for Economic Cooperation and Development's anti-bribery convention and had adapted its legislation accordingly.
But she claimed the new law was not being applied enough.
"Since 2000 we only have one single case in which a Swiss court convicted a defendant of bribing a foreign public official."
Monitoring and enforcement had to be more "rigorous", she argued.
However, she noted that the federal prosecutor had opened 22 cases in connection with the Oil for Food programme. This allowed Iraq to sell oil to finance the purchase of humanitarian goods and various United Nations activities concerning the country.
The Swiss cases involve Swiss-based companies that are alleged to have paid the Iraqi government hefty bribes between 1999 and 2003.
In its findings Transparency says overseas bribery by companies from the world's export giants is still common, despite international anti-bribery laws.
Code of conduct
Schwöbel commented that companies should have a code of conduct that applies to its businesses both at home and abroad.
"What we saw from the BPI is that Switzerland and other countries act differently in OECD countries than in countries with low incomes."
"We think that the responsibility lies also with companies to have one single message not to bribe and [this] has to be applied to all its subsidiaries," she said.
Schwöbel said that the index was intended to raise awareness of the situation, which showed that corruption was not only a problem in poor countries.
"Rich countries have their responsibilities and are not always good examples," she added.
swissinfo, Robert Brookes
Top Ten in the BPI
1) Switzerland: 7.81
2) Sweden: 7.62
3) Australia: 7.59
4) Austria: 7.5
5) Canada: 7.46
6) Britain: 7.39
7) Germany: 7.34
8) Netherlands: 7.28
9) Belgium and United States: 7.22
26) Taiwan 5.41
27) Turkey: 5.23
28) Russia: 5.16
29) China: 4.94
30) India: 4.62
Bribe Payers Index 2006
The index is a ranking of 30 leading exporting countries according to the tendency of their firms to bribe abroad.
The BPI 2006 was calculated using the scores given by 8,034 business people who offered an assessment of companies from at least one country.
A total of 11,232 people in 125 countries were surveyed but 3,198 (28%) did not offer an assessment on any country regarding the tendency of their companies to bribe abroad.