Over the past decades and in the course of a complex discourse, NATO has decided to undertake a role in energy security. From one perspective, the Alliance has already reached a kind of ‘acquis’ related to energy security, based on three strategic priorities: political consultation and intelligence sharing; projecting stability; and protection of nuclear and non-nuclear critical energy infrastructure. On the other hand, NATO’s current activities suggest that it will not take on a leading role, but rather a limited and complementary one. After analyzing the theoretical discourse around the emerging NATO agenda on energy security, the article addresses its practical implications for the South Caucasus. The article explores NATO’s possible contributions to the regional energy security. First, it examines the potential of a traditional deterrence-based approach, before assessing the forms of preventive approaches developed by NATO. The article concludes that cooperation in the framework of partnership programs has been developing in line with the functional security concept, increasing the partner states’ capability to respond to emerging energy security challenges, while also contributing to the security of NATO member states.