Author and eco-entrepreneur Roo Rogers' ventures include an alternative town-car service that uses hybrid cars. His recent book, "What's Mine is Yours," discusses collaborative consumption--bartering, trading,

and sharing, but on a massive scale. Examples include Ebay and Craigslist.

"Although there is no magic bullet, social entrepreneurship unlocks everybody's ability to be a change maker and to participate in the solutions to their own problems," says Susan Davis of BRAC, the world's largest development agency and a microfinance pioneer.

Can MBAs be held to "do no harm" standards similar to those of MDs? The MBA Oath was created by a group of Class of 2009 Graduates of Harvard Business School. Like the Hippocratic Oath made by doctors, the MBA Oath outlines values and ideals to which managers should commit.