This chapter examines growing concerns over global energy security due to rising demand for fossil fuels by industrialized economies coupled with increasing uncertainties over future energy reserves. It considers the implications of increasing energy insecurity amongst the world’s major powers for international security by focusing on the politics of oil. After providing an overview of the problem of energy security, the chapter discusses the connection between energy security and International Relations theories such as liberalism, realism, and historical materialism. It then explores the link between energy security and human insecurity, and how the search for energy security by states in the global North affects the human security of communities in the oil-rich global South. The chapter concludes with an analysis of the role played by the United States in underpinning global energy security in the post-war era, and the impact that this has had for oil-rich regions.