From the role of government to attitudes toward foreign investment and the nature of entrepreneurship, China and India differ in fundamental ways. Yet the future of these two cultures rests on a shared optimism of people on the streets, an outlook grounded in the belief that it is possible for individuals to work their way up the economic ladder—a notion that is expanding in China and India just as it is being challenged in the United States. So says Tarun Khanna, Harvard Business School professor and author of Billions of Entrepreneurs: How China and India Are Reshaping Their Future and Yours. The result is rapidly increasing cross-border trade and a growing trust built on familiarity that is reshaping their future—and the rest of the world’s.