European energy security challenges have changed dramatically in the past 20 years. On the one hand, the current tensions between Russia and the EU are undermining their historical partnership on energy; on the other, deep transformations in the energy landscape at the global level, triggered by technological advances and major geo-political transformations, are leading the EU to rethink its energy security strategy. The aim of this paper is to discuss European energy security in a changing global context and to analyse the tools and policies implemented to strengthen it. The role of potential future vectors of energy cooperation between the EU and its Mediterranean neighbours is also examined.