The Giving Pledge: Billionaires Promise to Donate at Least Half Their Fortunes to Charity

August 4, 2010— -- At the urging of Bill Gates and Warren Buffett, forty of the world's richest families have promised to give at least half of their fortunes to philanthropy.

By taking the "Giving Pledge," the forty families or individuals, most of whom are billionaires, are promising a collective sum of at least $125 billion to charitable causes, based on Forbes' current estimates of their net worth and other data sources.

Click here for the full list of donors.

On the whole, Americans have given more than $300 billion per year in recent years, though giving has declined since the start of the recession, according to the Giving USA Foundation.

"We're hoping that America, which is already the most generous society on Earth, becomes even more generous over time," Buffett told reporters on a conference call today. "More philanthropy and smarter philanthropy in the future is the goal."

Besides inspiring others to give, the pledged sums promise to make a huge impact.

"Private dollars are really special dollars because they provide the ability to innovate, to take risks, to think outside the box," said Gordon Campbell, president and CEO of United Way of New York. "Just think of the possibilities."

"I think it's a stopgap at a time when charities are facing a dip in income," said Jennifer Tierney, development director for Doctors Without Borders in the U.S. "It's a great way to fill the time between the recession and when the country gets back on its feet and your everyday American citizen is able to support in the same way that they have been able to in the past."

According to the pledge, the giving can occur either during donors' lifetimes or after their passing. Each has committed at least 50 percent of their net worth, but many have committed to larger percentages, Buffett said.

The men and women taking the pledge are free to direct their money to causes of their choice, and the organization is not pooling any money or dictating areas of need. In fact, the pledge is non-binding, though the organizers say the billionaires are making a "moral commitment," publicly signing their names to letters posted on a website, GivingPledge.org.