A method for selecting a communication system assigned to a transmission network of an automation system, where a transmission network with a plurality of subscribers, connected to the transmission network, of one or more automation systems is displayed, or is capable of being displayed, on a display unit. The transmission network is assigned to a plurality of communication systems, where the plurality of communication systems are each designed or configured for communication over the transmission network between at least two of the subscribers connected to the transmission network. By selecting a selection area assigned to the transmission network on the display unit by a selection device, the plurality of communication systems assigned to the transmission network are displayed on the display unit. Subsequent to selection of the selection area assigned to the transmission network by the selection means, one of the displayed communication systems is then selectable by means of the selection means.