New Zealand's ranking as the least corrupt country in the world comes as no surprise, but more can be done, the Chief Ombudsman says.
New Zealand has retained its ranking in the latest Transparency International index, edging out Denmark.
Countries were ranked by their perceived levels of public sector corruption according to experts and businesspeople, and rated on a scale of 0 to 100, where 0 is highly corrupt and 100 is very clean.
New Zealand scored 89 out of 100, down a point from the year before.
More than two thirds of the countries surveyed fell below 50.
Chief Ombudsman Peter Boshier said he wanted more protection for whistleblowers who did not feel confident reporting corruption.
"For those that want to report practice which is not correct, and who want to blow the whistle, should have better protection and better incentive than they have presently got now."
He said people often withold information about any wrong doing because they were afraid of the consequences they might face.
New Zealand has been ranked top or equal top in five of the past six annual surveys.
Those behind New Zealand in the top 10 included all the Scandinavian countries, Singapore, Switzerland, Holland and Canada.
Australia ranked 13th and was mentioned as a country where perceptions of corruption were rising, while the United States was 16.
The worst countries were those mired in civil war and conflict -- Somalia, South Sudan and Syria.
Last year a report by accounting firm Deloitte (https://www.radionz.co.nz/news/business/333491/corruption-is-real-in-new-zealand-it-s-happening) also ranked New Zealand and Denmark as the least corrupt countries, but noted that corruption in various forms such as conflicts of interests, gifts, and bribes were not uncommon.