This chapter explores the concept of societal security. It starts by looking at how society came to be conceived as a referent object of security in its own right. It then goes on to discuss the so-called Copenhagen School’s understanding of both society and societal identity, showing how societal security is tied most of all to the maintenance of ethno-national identities. In looking at threats to societal security, through examples, such as the former Yugoslavia and Northern Ireland, the chapter discusses a number of those means that can prevent or hinder the reproduction of collective identity, and, in turn, how societies may react to such perceived threats. The chapter concludes by considering some of the main critiques of the concept as an analytical tool.