Abstract: A GSM or UMTS mobile telecommunications network is disclosed. In addition to the conventional radio access network comprising the base stations, one or more additional access points are provided. An access point is connected to the network core by an IP transport broadband connection. The access point is configured to appear to the mobile terminal as a conventional base station—that is, it communicates with the mobile terminal using GSM or UMTS transport protocols and does not require any modification to a standard GSM or UMTS mobile terminal. Access Points are typically not under the direct control of the network provider. Arrangements are disclosed which allow the network provider to verify that the access point a mobile terminal is about to commence communicating through is at a particular location. Differential charging may be performed in dependence upon a subscriber's location.