Western Europe is a security community. In contrast to the expectations of most contemporary theorists of security communities, this has not been achieved by erecting common security structures or institutions, but primarily through a process of “desecuritization”, a progressive marginalization of mutual security concerns in favor of other issues. This chapter's main section traces how Western Europe has gone from insecurity (1940s and 1950s), over security (1960s) and desecuritization (1970s to the mid 1980s) to reach a situation in the 1990s of re-securitization. Mutual military fears are still absent at the level of state-to-state, but more issues are today cast in security terms, economy, environment and migration. Classical political security concerns appear but are mostly conceived for “Europe” not individual states. Re-securitization raises the specter of a possible unravelling of the West European security community, because when something is constituted as a security issue this enables more extreme action. Since Deutsch defines security community in terms of the absence of war, it really is a non-war-community, and security problems can continue to unfold within it.