This chapter explains why an understanding of the political economy of security is important, especially in East Asia. It details the geopolitical conditions that have made politics and economics such inextricably intertwined, mutually constitutive forces across the region. The historical experience of the East Asian half of the Asia-Pacific serves as a powerful reminder that international orders are ultimately social processes, which are realized within specific geopolitical circumstances. The chapter briefly introduces some of the more important theoretical innovations that have made the political economy perspective such an important part of contemporary debates about security and international relations. It gives more detailed consideration to the East Asian experience, explaining what is distinctive about it, as well as how and why East Asian political elites have been keen to promote and defend their approaches to development.