Abstract: A vehicle location determination system and method includes a vehicle-mounted position determining system, including a computer for executing position determining software, and at least one aiding data source such as a global positioning system (GPS) receiver, an odometer, gyroscope, a short-range radio link or a map database. In response to a request by a position determining entity (PDE) or other requesting entity a response is provided, which may include a computed pseudo-range to one or more GPS satellites.