In the international arena, it is often the case that in countries which largely depend on foreign resources, energy security, and its key components i.e. security of energy supply, environment, technology, geopolitical and economic factors, is a subject of concern. However, due to the abundance of fossil fuel resources in resource-rich exporting nations, there is a lack of understanding of the risks around energy security and accordingly often a policy vacuum. Conceptualising energy security from different geopolitical vantage points will allow future concerns around energy supply security, climate change, and regional economic crises to be evaluated. By using policy documents and developing a time series approach and normalized z-scores for a range of comparable metrics this article compares the energy security performance in six Caspian Sea countries individually and collectively. The article results show that Azerbaijan, Iran, Kazakhstan made significant progress in energy security since 1990, while energy security indicators in Russia, Uzbekistan, and Turkmenistan regressed. Iran has a leading position in energy security performance, while Uzbekistan and Turkmenistan have the lowest level of the energy security indicators compare to other region countries. This article both contributes a replicable definition of energy security that can be undertaken for other global regions, and begins to incorporate diversification and renewables development to enhance domestic energy security assessment.