GPRS roaming enables subscribers to access their GPRS services while abroad or beyond the reach of their home mobile network.

Roaming requires a connection be made between GPRS operators so that subscribers can move from one network to another and yet still access their GPRS service. The GSM Association recommends the use of a GPRS Roaming eXchange (GRX) for Inter-PMN GPRS roaming, as GPRS Roaming based solely on bilateral relationships between individual GPRS operators soon becomes incredibly complex and expensive to maintain once the number of roaming partners increases.

The GRX service provider acts as a hub, making it unnecessary for a GPRS operator to establish a dedicated connection to each roaming partner. Instead the GPRS operator establishes one connection to the GRX. This allows faster implementation of new roaming relations and rapid time to market for the new operator.

Furthermore, the services offered by the GRX allow the GPRS operator better scalability. The operator may start with a low capacity connection to the GRX and upgrade if volume and type of traffic require more bandwidth and better quality.