This thesis examines whether stabilization clauses continue to play a necessary and useful role in contemporary energy contracts. These clauses were traditionally employed to protect foreign investors from regulatory and political risks and were typical tools in agreements concerning capital-intensive energy projects. However, the constantly changing circumstances of international energy framework—characterized by climate promises, ESG concerns, and the need for state’s right to regulate - have generated an ongoing debate regarding their utility and effectiveness. The study begins in Chapter 1 by introducing the subject of the thesis, the research background, the research question, as well as the methodology and the structure. Chapter 2 analyzes the legal character, typology, and enforceability of stabilization clauses in international energy agreements. Subsequently, Chapter 3 examines the characteristics of modern energy contracts, such as Power Purchase Agreements (PPAs), Production Sharing Agreements (PSAs), and Contracts for Difference (CfDs), the current international environmental landscape and some relevant arbitral awards. Chapter 4 discusses the enforcement trends of stabilization clauses via several arbitral awards, as well as the interaction of stabilization clauses with the Fair and Equitable Treatment standard and State’s sovereign powers in the energy sector. Chapter 5 assesses whether alternative mechanisms, such as adaptation and renegotiation clauses, treaty-based protections and soft law principles, may offer more flexible and balanced solutions in the context of the global energy transition. Chapter 6 summarizes the main findings of the thesis and concludes that stabilization clauses are not considered obsolete nowadays, but their function has evolved.