The Conclusion examines the nature and scope of diplomatic security policies worldwide, the factors underlying their variations, their effectiveness in securing diplomats, and their implications for the conduct of diplomacy. It provides novel insights into the study of security and diplomacy alike. Most notably, it underscores the importance of organizational interests and cultures in shaping protective arrangements, conceptualizes diplomatic inviolability as an international norm, and posits the existence of a trade-off between effective diplomacy and effective diplomatic security. Arguing that diplomacy in a traditional sense has partly lost its importance has become commonplace. States’ reluctance to close missions in dangerous locations, arguably the most effective security policy available, vindicates the enduring importance of traditional, face-to-face diplomacy in the twenty-first century.