This book, drawing on fresh scholarship, investigates electrification in new places and across different time periods. While much of our understanding of electrification as a historical process is based on the seminal work done by Thomas P. Hughes in Networks of Power (1983), the scholars in this volume expand and revise Hughes' systems approach to suggest that electrification is a heterogeneous and contingent process. Moreover, the contributors suggest that the conquest of the world by electricity remains incomplete despite more than a century elapsing. Above all, though, this book provides context for thinking about what lies ahead as humans continue their conquest of the earth through electricity. As we become increasingly dependent on electricity to power our lights, heat and cool our homes, turn the wheels of industry, and keep our information systems humming, so we are ever more vulnerable when the grid runs into trouble.