A system includes a plurality of control devices that respectively control the states of a plurality of apparatuses and are connected to each other via communication lines. When each of the control devices determines a state target value of its own apparatus using the current state indicator value of the own apparatus, and the distributed controller input which is a function of the state indicator value of an apparatus adjacent to the own apparatus and the state indicator value of the own apparatus, the control gain which adjusts contribution of the distributed controller input to the state target value is determined based on a communication delay time between the control devices.