This chapter presents an overview of how a hydrogen economy can be realized. We will give an overview of the principles of hydrogen energy production, storage, and utilization. We will also discuss different aspects of hydrogen safety. Hydrogen production will cover a whole array of methods including electrolysis, thermolysis, photolysis, thermochemical cycles, and production from biomass. Hydrogen storage will cover all modes of gaseous, liquid, slush, and metal hydride storage. Hydrogen utilization will focus on a large cross section of applications such as fuel cells and catalytic combustion of hydrogen. Details of many of these topics will be presented in the rest of the handbook.