Energy security (ES) has become a critical concern in the face of rising energy demand, climate change, and tightening environmental regulations. While renewable energy sources offer a sustainable solution, various barriers hinder their effective utilization, especially in emerging economies. These obstacles limit the successful transition from conventional, non-renewable energy sources to more sustainable alternatives. This chapter aims to systematically identify and prioritize the key barriers affecting energy security in developing nations. Using the Decision-Making Trial and Evaluation Laboratory (DEMATEL) method, the study analyzes and ranks the critical barriers that demand immediate attention. The approach helps uncover the complex causal relationships among the identified barriers, offering a structured way to understand their interdependencies. By highlighting which barriers are the root causes and which are outcomes, the model supports more strategic policymaking and planning. The resulting decision-support framework serves as a robust, practical tool for stakeholders to implement targeted solutions and enhance energy security. This analysis is especially valuable for governments, energy planners, and sustainability advocates working to achieve resilient, clean, and efficient energy systems in rapidly growing economies.