Examines the concepts designed to explain the nature of contemporary international relations, including: the emergence of the discipline and the nature of its subject matter, key agential concepts in IR (state, empire, international and subnational agents and foreign policy), key structural concepts in IR (the states system, Euro-centrism, globalisation, post-colonialism, global governance and security), key institutional concepts in IR (international society, great powers, diplomacy, war, balance of power, international law and human rights) and key sociological concepts in IR (power and sovereignty, intervention, gender and anarchy).