A method and system for locating a mobile-subscriber terminal (MST) roaming in a serving network is provided. A location based service provider (LBSP) that is outside of the serving network receives from the serving system an MST-initiated request for providing location based services (LBSs) and an identifier of a first location system (LS1) that is associated with the serving network. Responsive to the MST-initiated request, the LBSP sends to a second location system (LS2) (i) a request for mobile positioning information (MPI) for the MST, and (ii) the identifier. Using the identifier, the LS2 addresses and sends the request for MPI to the LS1. Responsively, the LS1 sends to the LS2 the MPI. The LS2 then send the MPI to the LBSP, which in turn sends to the MST a reply to the MST-initiated request for LBSs.