Global politics (or world politics) covers all aspects of politics that affect multiple political systems, in practice meaning any political phenomenon crossing national borders. This can include cities, nation-states, multinational corporations, non-governmental organizations, and/or international organizations. An important element is international relations: the relations between nation-states may be peaceful when they are conducted through diplomacy, or they may be violent, which is described as war. States that are able to exert strong international influence are referred to as superpowers, whereas less-powerful ones may be called regional or middle powers. The international system of power is called the world order, which is affected by the balance of power that defines the degree of polarity in the system. Emerging powers are potentially destabilizing to it, especially if they display revanchism or irredentism.

Politics inside the limits of political systems, which in contemporary context correspond to national borders, are referred to as domestic politics. This includes most forms of public policy, such as social policy, economic policy, or law enforcement, which are executed by the state bureaucracy.