Why do great powers accommodate the rise of some challengers but contain and confront others, even at the risk of war? proposes that the ways in which a rising power legitimizes its expansionist aims significantly shapes great power responses. Stacie E. Goddard theorizes that when faced with a new challenger, great powers will attempt to divine the challenger’s intentions: does it pose a revolutionary threat to the system or can it be incorporated into the existing international order? Goddard departs from conventional theories of international relations by arguing that great powers come to understand a contender’s intentions not only through objective capabilities or costly signals but by observing how a rising power justifies its behavior to its audience. To understand the dynamics of rising powers, then, we must take seriously the role of legitimacy in international relations.