Architecture has emerged as the new catchphrase in Asian security politics. Despite its growing centrality, insufficient attention has thus far been given to defining the term, often leading to its imprecise usage. This article seeks to redress that shortcoming. It reviews the ways in which various scholars and practitioners have employed the term security architecture and highlights the anomalies that their often differing employment has created. The article proposes a set of guidelines to aid conceptualisation and application of the term. In so doing it establishes criteria to ascertain what security architecture actually exists in the Asian region, and must ultimately exist to assure regional security.