This paper describes the system architecture and functional specifications of Distribution System Operator (DSO) and Transmission System Operator (TSO) control systems needed for the management of active grids exploiting distributed generation, storage and load/storage flexibilities and AD on distribution networks (Medium Voltage (MV) and Low Voltage (LV)). In particular, to both enable and exploit the flexibilities and services provided by massive demand side participation, distribution network management has to be substantially enhanced by introducing new functions at the DSO Control Centre level as well as by decentralizing intelligence.