Neutrality as a concept and practice has long been conceptualised in IR theory as problematic. Broadly seen as the tool of small and weak states with dubious moral credentials, a limited understanding of neutrality has persisted from the Peloponnesian War to the ‘war on terror’. Furthermore, as globalisation and non-traditional security problems animate international politics, neutrality is seen as a policy of the past. This book argues that neutrality has been a neglected and misunderstood subject, limited to realist understandings of war and viable statecraft, and in doing so aims to uncover the normative strands of neutrality that mesh with identity, security and alternatives to the anarchic international order. Using Sweden as a case study, it explores the domestic roots of neutrality via a constructivist analysis, examining how neutrality is embedded in ideas of self, and part of a wider Social Democratic vision of active internationalism. Identity, however, is malleable and subject to change, and this analysis also considers the impact of globalisation and European integration, the end of bipolarity, and new security threats such as global terrorism on neutrality as an idea and a practice.