A system and method of mobile communication roaming where a subscriber's home network and a roaming network used by the subscriber do not have a roaming agreement. The roaming network sends a “Send Authentication/Parameters” request to the home network via an intelligent roaming system on or attached to the backbone. The home network sends an authentication response to the “Send Authentication/Parameters” request from the home network to the roaming network via the backbone and intelligent roaming system. The roaming network sends a “Update Location” request from the roaming network to the intelligent roaming system. The visitor locator register (VLR) address in the “Update Location” request is replaced with the VLR address of the intelligent roaming system to create a modified update request. The modified update request is sent from the intelligent roaming system to the home network. The home network sends an update response to the modified update request to the roaming network via the backbone and intelligent roaming system.