Gateway apparatus is described for interconnecting at least first and second signalling networks with an application server process via a third network, the apparatus comprising: a plurality of signalling gateways, with at least one signalling gateway coupled to each signalling network; and a proxy element for transferring signalling messages between the signalling gateways and the application server process via the third network. The first and second signalling networks may be separate signalling system 7 (SS7) networks and the third network may be an internet protocol network.