A welcome effort to assess the implications of unipolarity in a collection of eclectic and thoughtful articles on realism. Several essays offer important amendments to the realist canon. Michael Mastanduno writes that other states will not automatically balance against a preponderant America; instead, such balancing will depend on America's behavior, not just its power, making diplomacy critical in managing unipolarity. Randall Schweller explores the role that status competition will play in triggering rivalry, while Jonathan Kirshner examines the geopolitical consequences of increasing economic competition. Other essays rebut the notion that unipolarity best explains current international stability. Daniel Deudney and G. John Ikenberry contend that economic openness, constraining international institutions, and the semisovereign status of major powers like Germany and Japan are in fact the key sources of long-term stability. And Alistair Johnson questions traditional conceptions of power-balancing by introducing the notion of "identity realism," arguing that China's behavior is best explained by elite efforts to strengthen the state and rally popular loyalty, not to balance against the United States. In sum, essential reading for those seeking to understand the current strategic landscape and its future.