Every state's foreign policy has to deal with other states, regions, and transnational issues, not all of whom are likely to receive the same level of policy-making interest and attention. States have differing foreign policy priorities, but how do we conceptualize those different priorities? To explain how states order the world and prioritize their foreign policy, I establish an ideal typology of “core” and “peripheral” foreign policy, which categorizes more and less important foreign policy spaces and issues. This typology contributes to foreign policy analysis's “middle-range” theorizing by establishing how and why the determinants, processes, and goals of foreign policy–making in these distinct types differ, and where policy-makers have the greatest ability to influence change in foreign policy. One of the key insights of this research relates to how structure and agency differently influence foreign policy–making: “core” foreign policy tends to be more structurally rigid and obtrusive, allowing less maneuverability for actor agency seeking to change the status quo, while “peripheral” foreign policy is less structurally rigid and obtrusive, allowing for greater actor agency in changing foreign policy direction and priorities. Hence, this typology should aid our understanding and prediction of foreign policy priorities and decisions.