In this book Gary Goertz examines how states interact with their environment and contexts, which are important in understanding international politics. He presents a philosophical, methodological and empirical discussion of three important contexts which affect decision makers: history, system structure, and international norms. The effects of these contexts are explored by viewing context in turn as cause, as changing meaning, and as a barrier. The book engages with the literature on structural realism and international regimes, and uses rational actor and diffusion models as theoretical references. A number of concrete studies are provided using these contextual tools, including oil nationalisation, USSR-East European relations, enduring rivalries, and decolonisation. These empirical examples illustrate the fruitfulness of the contextual approach to international politics.