The field of Road Transport Informatics (RTI) has spurred a substantial interest in the development and adaptation of a diverse range of technologies for vehicle-infrastructure communications. Candidate technologies for early implementation include FM RDS-TMC, short-range beacons and cellular mobile radio GSM. This paper reviews some of the major characteristics of these systems and debates some of the issues influencing the design and integration of communications technologies for RTI. Next, a possible integration framework which essentially acts to decouple RTI applications from communications networks is described. The aim is to facilitate end-to-end communications between any two application systems which need to communicate, regardless of the network to which each is attached. This concept leads to the notion of a virtual RTI network and is currently under investigation to determine its viability and applicability.