Power and leadership are among the central features of politics. They become even more visible in an environment such as the international system that lacks strong institutions. Without legislatures or administrative organs in a normal sense, political processes such as leadership, persuasion, and coercion come to the fore.These processes, especially the question of leadership, are central to many policy questions. Is Franco-German leadership of the European Union breaking up, or will it be joined by a more Europhile Britain? How will China or Japan play a leadership role in East Asia?Nowhere is the question of leadership more discussed than in the case of the most powerful country in the world – once the United Kingdom, today the United States, perhaps one day China. For some people, the leadership of this "hegemon" helps bring peace and prosperity to the world as a whole; for others, its dominance is overbearing and illegitimate.Questions of hegemony have received significant academic attention over the past few decades. This chapter will review the North American literature on the topic, with an eye toward several questions. First, what does a hegemon do when it is being hegemonic? Second, how do non-hegemonic countries respond to its leadership? Third, and most important for the future, is hegemony good or bad for the international system? I will discuss these with reference to topics in political economy, setting aside an equally-large literature on the military consequences of hegemony. Though political economy has implications for ideology and discourse, this article will also set aside most of these issues, which have sparked a large and distinct literature of their own.