This article explores issues of energy supply security from the perspective of the EU–Russian energy relationship and of competing foreign energy policy paradigms. Using approaches developed by Peter Rutland within the context of Russia's energy policy towards the CIS and the three pillars of EU energy policy as a starting point, the article concludes that the overall EU–Russian energy relationship can be best explained through a framework of mutual interest and dependency: that is, the EU is becoming increasingly, but not totally, dependent on Russian energy, particularly gas; and Russia is becoming increasingly, but not totally, dependent on European markets. Nevertheless, other paradigms continue to yield useful insights in relation to individual components of the EU–Russian energy relationship.