The changing political and social meanings of space under conditions of advanced globalization point to the need to analyze security - or the deployment and management of violence - as a socio-spatial practice. This article draws attention to the "methodological nationalist’ bias that has traditionally characterized mainstream security studies, and discusses its effect on how security issues are studied and conceptualized. Building on insights from political geography and sociology, the article makes the case for a " spatial turn " in the field. It demonstrates how a socio-spatial approach can help make sense of evolving state security practices, and presents examples of non-national spaces of security - including cities, cyberspace, and the global polity. Such spaces are increasingly objects of security practices, although the implications of this remain largely under-theorized in security studies.