Michael Hardt and Antonio Negri’s book Empire has been hailed as a latter day Communist Manifesto. Its ability to develop a theoretical framework relevant to the current period of global neo-liberalism and international capitalism captured the imagination of the growing anti-capitalist movement and has been claimed as a turning point for the left. As much as it has seduced and delighted some, however, it has enraged and frustrated others. In this collection, a series of some of the most acute international theorists and commentators of our times subject the book to trenchant and probing analysis from political, economic and philosophical perspectives, and Hardt and Negri respond to their questions and criticisms.