Abstract: A technique for enabling a peregrinating Cellular Mobile Radiotelephone (CMR) subscriber to automatically receive, in a foreign service area (that is, an area outside his home service area), calls placed to his MID at his home service area. A roaming processor is coupled through a cable or LAN to a switch associated with a foreign MTSO and is coupled, preferably through a private data network, to a switch associated with the subscriber's home MTSO. Within the roaming processor resides a program that detects the reception at the foreign switch of a predetermined code indicating that calls placed to the roamer's home MID are to be forwarded to the foreign MTSO. Subsequent to the "validation" of the roamer and to the performance of certain software housekeeping tasks, the roamer is assigned a Temporary Directory Number (TDN) for use in the remote service area. The FMR processor then commands the subscriber's home MTSO switch to forward calls, placed to the subscriber's MID at the home MTSO, to the TDN.