Transcript for World's Wealthiest Donate Billions Through the 'Giving Pledge'
of America's wealthiest families have been leading a new philanthropic movement, it's called the giving pledge, its goal -- to channel the billions held by the richest of the rich, back to the people who need it most. ABC's Rebecca Jarvis sat down with the pledge founders, Warren Buffett and bill and Melinda Gates to track the progress. Reporter: They hang out with rock stars. Even presidents. He's so thrifty I had to give him a white house tie. When bill Gates came he wanted one, too. Reporter: But for the past five years, these billionaires have focused on a remarkable mission -- giving away their massive fortunes to charity. You decided to give away 99%. Of your wealth. Other people can buy vacsci vaccines. It can buy education. Besides, you know, 20 years from now, I'll be in a place where there will be no form 400. Reporter: We visited Warren Buffett and bill and Melinda Gates to talk about the giving pledge and the challenges ahead. I have been amazed. How receptive people have been. Reporter: What began as 40 billionaires pledging to donate at least half their money has tripled. 135 individuals from 14 countries. A total of $1 trillion in commitments from the likes of Facebook's mark Zuckerberg, Richard Branson. These people are giving a minimum of 500 -- Reporter: You're surprised? I have got an fair number of nos. We had no idea that we would get this many people to come together. Reporter: Tackling issues like poverty, education and disease, where they have seen considerable success. Polio is likely to become the second disease ever eradicated and then we'll take that success and go after other diseases like malaria. We expect to cut the number of children who die, which is 6 million a year in half over this next 15 years. Reporter: What has the most pressing urgent need today? How do we empower women and girls, they're at the center of the families. Reporter: Of the world's 1800 billionaires, 7% have signed the pledge, getting more new faces onboard, particularly international donors is a top priority. I do want to hear the elevator pitch. What do you say? I just say, hi, Rebecca, what are you thinking about doing with all of that wealth that you got? You're not going to live forever. Do you really think your children are going to be better off if they each have $500 million -- Reporter: The pledge is not a legally binding document. Those who take it can give today or put it in their will. You can't really say to people, give it all away while you're alive, because you don't know how long you're going to live. The sooner the better. Encouraging people that it's fun. As Warren likes to say, the younger you are and more vibrant and clever about your giving you'd like to be. He has a more colorful -- If I get some 75-year-old saying he'll think about it later, you know, I ask him, do you think you can come with a better decision when you're 95 years old? Reporter: The newest member to join the pledge is just 43, the founder of chobani yogurt. He has an estimated $1.4 billion. When I get to know what bill Gates do and Warren Buffett, I wanted to do the same way that they did. Reporter: His charity will go toward helping refugees around the world. You can save a life, you can make somebody's life better. Why put it somewhere and wait for 70 years while you can do it right now. Reporter: How has it changed philanthropy and giving in this country? To do it at a younger age and to be more bold, because they find people with similar causes in mind. I want people to say that it's the right thing to do. Reporter: For "This week," Rebecca Jarvis, ABC news, new York. Thanks to Rebecca for that.
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