For philanthropists of the past, charity was often a matter of simply giving money away. For the philanthrocapitalists—the new generation of billionaires who are reshaping the way they give—it's like business. Largely trained in the corporate world, these "social investors" are using big-business-style strategies and expecting results and accountability to match. Bill Gates, the world's richest man, is leading the way: he has promised his entire fortune to finding a cure for the diseases that kill millions of children in the poorest countries in the world.

In Philanthrocapitalism, Matthew Bishop and Michael Green examine this new movement and its implications. Proceeding from interviews with some of the most powerful people on the planet—including Gates, Bill Clinton, Warren Buffett, Oprah Winfrey, and Bono, among others—they show how a web of wealthy, motivated donors has set out to change the world.