I am worried about the swindlers that live among us. They steal a huge amount of money.

Think of the sensational story of Australian Melissa Caddick.

She allegedly swindled family members, friends, and others out of tens of millions of dollars.

Her alleged scheme is a tried and true one, known as the Ponzi (pronounced pon-zee).

A Ponzi scheme involves promising huge returns on investments, and then providing high returns by giving investors a chunk of their own money back each year.

To keep the practice going, the schemer must continually add money from new investors.

Eventually, the scheme collapses because there is no real income, and too many investors ask for their money back.

The schemer cannot return the investments, because he or she has spent almost all of it on high living. Investors typically lose their entire investment.

Caddick disappeared soon after police visited her with a search warrant late last year. Later, what was believed to have been her foot was found in a running shoe on an ocean shore.

The original Ponzi, Charles, was an Italian-born man who swindled people in North America.

Give him credit for creative swindling and for making his name immortal.

He swindled folks out of oodles of money and then spent years in prison.

Upon release, he encountered an angry mob of people he had swindled. The US deported him, and he died in poverty.

The modern face of the Ponzi scheme worldwide is that of Bernie Madoff. He once ran the NASDAQ stock market.

Later, he swindled friends and others in the largest Ponzi scheme in history - stealing tens of billions of dollars.

Madoff died in an American prison earlier this year.

So, how can you and I avoid getting scammed?

My advice is first, if something to do with money seems too good to be true, figure that it probably isn't.

Second, be careful with your dough - collect all the information you can like a detective before you invest any money.

John Malouff is an Associate Professor at the School of Psychology, University of New England.