European security is a complex network of insecurities, institutions and initiatives. Europe is faced with the traditional insecurities of inter- and intra-state conflict as well as non-state threats to security such as environmental, health and human security. The region's attempts to combat these insecurities have been to develop and foster regional institutions, such as the EU, NATO, OSCE and even the Council of Europe. In turn, member-states and the institutions have set out various ways to combat a range of insecurities from ethnic conflict to human trafficking. This text explores the complex European security architecture with an eye on introducing students to the empirical, theoretical and conceptual approaches to European security.