This chapter demonstrates how current developments in European security in the European Union (EU) and beyond affect Irish neutrality, and analyses the compatibility of Irish neutrality with current and future developments in this area. It describes an assessment of the level of Irish engagement in European security developments since 1992, linking this with neutrality in order to determine whether neutrality has constrained Irish participation in European security structures. The chapter argues that Irish neutrality is compatible with developments in European security, including in the EU context, in the short to medium term. The new European security order constructed after the end of the Cold War has severely tested the adaptive abilities of the security policies of all the European neutrals, Austria, Sweden, Finland, Switzerland and Ireland. The chapter also presents an overview of the key concepts discussed in this book.