Book excerpt: Stuck in the middle of different as well as relevant regional complexes, the Caspian Sea basin represents a critical geopolitical hub in the heart of Eurasia landmass. Political, economic as well as strategic considerations contribute to determine the systemic relevance of the Caspian Sea, whose reputation in the West is mainly linked to the vast availability of largely untapped oil and gas resources. However, behind the fierce competition aimed at the exploitation and transportation of the basin’s hydrocarbons lies a much more complex picture, consisting of interlinked legal, military and soft power issues and threats. Aim of the volume – result of a joint research project conducted by the Center for Strategic Studies under the President of the Republic of Azerbaijan (SAM, Baku) and the Institute for International Political Studies (ISPI, Milan) – is to address the relevance of the Caspian Sea in the post-bipolar international system, analyzing both soft and had security threats emerging form the basin, as well as the policies of littoral and extra-regional actors.