We seek to find the factors that influence European Union member states' support for a common natural gas strategy. Even though the EU already expressed its will to act in energy issues, member states' national interests still prevent a coherent energy policy from being implemented. We test three member states with the LIG theory, which considers that groups that represent economic and industrial interests are the most influential on their national foreign policy. We compare this theory with realist and constructivist approaches and conclude that the level of gas import dependency and national identity factors are less influent on state support to the common policy than is the level of investment of national energy champions in the Russian gas sector.