This chapter analyses the role of electricity storage as an innovative strategy to attain the Mexican Government’s goals regarding carbon dioxide emission reduction and energy transition. The survey includes the analysis of the different electricity storage technologies as well as the legal framework governing electricity storage as the fifth link of the energy supply chain from a comparative perspective. The authors discuss whether energy storage is a generation or a distribution/transmission asset. The chapter also analyses Mexico’s experiences in energy storage and briefly describes the way it is regulated in other jurisdictions. Finally, the authors propose the regulation of energy storage as a separate licensed activity.