In addition to his work in founding the Grameen Bank, for which he was awarded the 2006 Nobel Prize in Peace, Professor Muhammad Yunus has devoted his recent work to spreading and implementing his idea of social business: a concept for businesses that strive to solve social problems, but are also financially selfsustainable. A social business pays back only its original investment and reinvests its profits in innovations or further growth that advance its social goals. In this lecture, Prof. Yunus examines the history and the future of the field of social business.