"No man is an island entire of itself; every man is a piece of the continent, a part of the main…." –John Donne, 17th-century English poet Economies are networks of businesses, just as businesses are networks of people, and people are networks of cells. Networks are everywhere, and the Media Lab’s fall sponsor event celebrated their ubiquity by exploring how these structured interactions affect our economy, businesses, health, and even the way we understand ourselves. How is the fate of one company connected to that of other businesses? How does the health of one individual affect that of his or her community? How do we make sense of a world that is becoming increasingly more connected–a world where complexity has become increasingly difficult to understand and manage?