Abstract: A control system for a power network, the control system comprising at least one monitoring device or constraint controller for monitoring, determining or measuring at least one parameter of one or more points, such as constraint locations, on the power network; and one or more device controllers for controlling at least one device connected or connectable to the power network; wherein the at least one monitoring device is configured to broadcast a request or objective based and/or dependent on the at least one measured or monitored parameter. The one or more device controllers are configured to receive or retrieve the broadcast request or objective and to determine a control action for the at least one device at least partially based on the request or objective. In this way, the control system may logically separate the determining of a condition of the point on the network from the decision of how to control the devices in order to resolve the condition.