Key Points:

A Kiwi who has made a billion-dollar fortune in Russia believes New Zealand is losing its way and squandering its potential.

Taranaki-born Stephen Jennings, who lives in Russia, is one of New Zealand's richest men. His wealth was estimated at $5.2 billion by Forbes magazine last month.

Mr Jennings told the Weekend Herald no other comparable country had as many young people living and working overseas - and isolation was not an excuse.

People weren't leaving Iceland or Perth, which were also isolated.

"The most damning indicator is when people vote with their feet and leave the country. We have to face the reality that our people are leaving the country because there is somewhere else they want to live."

Mr Jennings, 48, is chairman and chief executive of Renaissance Group, a finance company he founded in Russia in 1995 as communism gave way to capitalism.

It has a consumer finance division with 12,000 employees, investments including the biggest land-holding in Ukraine and the largest forest estate in Russia, and is expanding into Africa.

Forbes' $5.2 billion boosts its earlier estimates of $1.6 billion, and puts Mr Jennings close to Graeme Hart, who the National Business Review Rich List says is New Zealand's richest man, with $6 billion.

Mr Jennings said the world's developing economies were growing at an unprecedented rate, and New Zealand needed a more entrepreneurial economy to keep up.

He advocated reducing the size of government, changing the welfare system, reducing taxes and debating "sacred cows" such as the health system.

Mr Jennings seldom gives interviews, but said he was prepared to sacrifice his low profile to pass on his beliefs. He will give the annual Business Roundtable Sir Ronald Trotter lecture next month.

"It's easy to grizzle at the barbecue - I'd rather stand up and say what I think."

Mr Jennings, who employs former All Black captain Sean Fitzpatrick in London, said the All Blacks were one area "we have consistently achieved, are recognised, have a global brand, and where there are high levels of professionalism".

"How many industries are there in the world where our professionals are the most sought-after professionals in the world? Our yachtsmen and our rugby players. They do it against countries with resources. They have a culture where they put that out of their mind and say, 'What is it about us that makes us better?' "

This was an "an incredibly powerful way of thinking".

"If New Zealand business and entrepreneurs think that way, especially in a world where everything is open, we can really be successful."

Mr Jennings returns to New Zealand two or three times a year and has a beachfront property on Oakura Beach, 12km southwest of New Plymouth, where he grew up.