The Concert of Europe, which was a method rather than a system, was Europe’s response to rifts in the Empire and to the havoc wreaked by wars of revolution. The Concert was based on balance and a joint study of issues ; it thus established a mutual watch between greater States and also offered some kind of protection to smaller States. Conceived as an instrument for legitimist conservatism, the Concert has been appropriated by liberalism and appears as a precursor both of the idea of European unity and modern multilateralism. It managed to endure even when rival alliance systems, which contradicted its spirit, were created in Europe. It was not until the last moment that antagonism between alliance systems and the Concert of Europe’s practices was to be resolved – that is to say at the outbreak of the First World War.