As the likelihood increases that Russia will dominate the European Union's (EU) energy supply, questions have emerged as to whether Russia would use the energy weapon to influence EU member policies and extract political concessions. Countervailing voices argue that Russia would be restricted by interdependence and market forces. As of yet, no one has analyzed the assumptions underlying the energy weapon thesis. Moreover, many scholars examining EU-Russian energy relations rely on non-Russian data. This article seeks to fill several informational and theoretical gaps by including Russian sources and first-hand data and by systematically analyzing the conditions that must obtain before an energy supplier can successfully convert its energy resources into political power. The resulting model can be utilized to analyze the capacity of a supplier to use the energy weapon-whether it be Russia, Iran, Venezuela or any other energy heavyweight-and to assess whether the deployment was successful. Five purported cases of Russian manipulation are analyzed in this article and the findings indicate that, more often than not, Russia failed to achieve political concessions. Looking to the future. the plausibility of Russia using the energy weapon to exploit Europe's dependence, particularly on gas, is also examined. (C) 2011 Elsevier Ltd. All rights reserved.