A system and method for determining the location of a target mobile device in a communications network. A set of mobile devices in proximity to the target mobile device may be determined (210) as a function of a common parameter of information observed by mobile devices in the set. Measurement data may be shared (220) for the set of mobile devices and the target mobile device, and a location of the target mobile device (230) determined as a function of the shared measurement data. This sharing of measurement data may occur amongst the set of mobile devices and the target mobile device or may also occur at a communication network entity.