This book presents a set of proposals for advanced control functionalities in order to achieve a coordinated and optimized voltage management of distribution networks comprising several Distributed Generation units, controllable loads, storage devices and microgrids. Large scale integration of Distributed Energy Resources, namely Distributed Generation at the Medium Voltage level and microgeneration at the Low Voltage level, poses several technical challenges for distribution network operation, especially concerning voltage control. Accordingly, the development of specific control solutions is required in order to maximize the integration of these units in the distribution system. The work presented here focused on the development of a conceptual framework model for regional ancillary services markets for voltage control. In addition, a methodology for voltage and reactive power control to be integrated in a tool for managing network operation in the short-term time-horizon is proposed.