Book excerpt: Current events happening around the world, especially the ’humanitarian interventions’ by NATO and the West within the context of the so-called Arab Spring, make the understanding of the role of spheres of influence in international politics absolutely critical. Hast explores the practical implications and applications of this theory, challenging the concept by using historical examples such as suzerainty and colonialism, as well as the emergence of a hierarchical international order. This study further connects the English School tradition, post-war international order, the Cold War and images of Russia with the concept of the sphere of influence to initiate debate and provide a fresh outlook on a concept which has little recent attention.