The traditional conception of agency in international relations has been narrow and Western-centric. This conception often conflates power with agency and focuses on material capabilities at the expense of ideational ones. Agency is not just about problem-solving ability, but also about resistance, contestation, agenda-setting, and different forms of norm propagation, including localization and subsidiarity. Such agency does not necessarily rely on material power. I illustrate these broader and diverse forms of agency with reference to the evolution of sovereignty and security in international relations. Regional frameworks of non-intervention, responsible sovereignty, non-traditional security and human security highlight the agency of less powerful actors, including non-Western states, and have played a vital but poorly recognized role in the construction of global order.