The chapter introduces strategic opportunity as the analytical approach guiding the book. China’s strategic opportunity is defined by the national goals and ambitions as set by the Chinese leadership, the opportunities and risks presented in the international environment, and the policy instruments and resources at the nation’s disposal. The chapter first shows how the concept is anchored in the reformist Chinese leader Deng Xiaoping’s assessment that peace and development were the predominant trends in the world. It then explains why the concept provides an appropriate and innovative approach to the study of Chinese foreign policy. Finally, the chapter investigates how Chinese leadership under Xi Jinping has launched a major-power diplomacy seeking to effectively deploy its newfound resources to reshape its international environment. It also lays out the salient causal beliefs and policy patterns behind the assertive Chinese foreign policy and concludes with a summary of the contents of the book.