On a worldwide basis, the development of SmartGrids is a consistent answer to the problem of an efficient and sustainable delivery of electric energy through distribution grids. SmartGrids are a combination of information and communication technologies and new energy technologies. There are many different definitions of the concept of SmartGrids and thus it appears indispensable to gather the knowledge available from both industry and research laboratories in one book. Distributed generation is rightly receiving an increased amount of attention and will become an integral part of urban energy systems, providing consumers and energy providers with safe, affordable, clean, reliable, flexible and readily-accessible energy services. The aim of this book is to describe future electricity networks that will enable all energy services to become sustainable. The traditional design of network control systems with a centralized structure is not in-line with the paradigm of the unbundled electricity system and decentralized control; this is highlighted by looking at how future active networks will efficiently link small- and medium-scale power sources with consumer demands, allowing decisions to be made on how best to operate in real time. It also looks at the level of control required: power flow assessment, voltage control and protection require cost-competitive technologies and new communication systems with more sensors and actuators than presently used, certainly in relation to the distribution systems. To manage active networks, a vision of grid computing is created that assures universal access to computing resources. An intelligent grid infrastructure gives more flexibility concerning demand and supply, providing new instruments for optimal and cost-effective grid operation at the same time.