AMK hopes that number will rise to 100,000 by 2008.

Luchtenburg is not new to Cambodia. He moved there 14 years ago, working for the US aid organisation World Relief, after a stint in Mexico.

He met his wife there and though raised in Chicago considers himself half-Cambodian.

Arriving after the war-torn country held its first democratic election after its society was shattered by war and the genocidal rule of the Khmer Rouge, Luchtenburg has been helping Cambodians take a step towards prosperity by helping them arrange loans as small as $50, in what he calls the microfinance industry. In 2005 Cambodia's per capita GDP was around a dollar a day.

Microfinance has become more mainstream as an alternative to simple direct assistance, particularly since Bangladeshi economist Muhammad Yunus was awarded the 2006 Nobel peace prize for his pioneering development of programmes offering relatively small loans to entrepreneurs in the world's poorest countries who could not otherwise get access to credit.

When asked how poor the clients AMK serves actually are, Luchtenburg tells the story of his visit to a village in the northern province of Preah Viheah.

"I was meeting a new group, just making their second repayment. AMK wants to work with poor people, I said.

Is there anyone in this community who wanted a loan but was too poor to get one. I said, if you don't mind me asking, who is the poorest person here? Unlike here, Cambodians don't mind people asking that.

"One woman says, 'Well, I'm the poorest'."Luchtenburg's voice cracks. "She was a widow, no family. She was 73 years old. She said, 'I'm a day labourer.' She took a loan of $15. I was a bit sceptical. It was one among 83,000. But it reassured me that we aren't excluding anyone, and this person really, desperately needed it."

People might ask, why don't you simply give that poor woman that money? Luchtenburg says the effect of treating a person not as a problem to be managed but as an equal is transformative.

"I'm not treating you like a beggar, I'm not treating you like a child, I'm treating you as an equal, " he says.

Charging interest to borrowers has not only been shown to be successful in individual cases but has allowed AMK now to operate in the black. It will be borrowing more funds on commercial terms.

One challenge facing Luchtenburg is his competition . . .AMK is one of nine major microfinance operations competing to offer services to Cambodians, though he says Concern's subsidiary is the only one focused primarily on the country's rural areas.

Another, more serious, challenge could be that the global low interest rate environment has now made a definitive turn towards higher interest rates.