A location server configured to cooperate with infrastructure equipment of a wireless communications network, the infrastructure equipment being configured to transmit signals to and receive signals from communications devices via a wireless access interface to transmit data to and to receive data from the communication devices, the wireless access interface being divided into a plurality of time units each providing time and frequency resources for transmitting the signals and receiving the signals and a plurality of the time divided units include positioning reference signals which are transmitted by the infrastructure equipment, the location server comprising a controller configured to determine a location of the communications devices with respect to a location of the infrastructure equipment from observed time differences between receiving the positioning reference signals transmitted by a plurality of the infrastructure equipment, and a connecting interface with the wireless communications network configured to receive reports of the observed time differences from the communications devices and to transmit control information to the plurality of the infrastructure equipment, and the controller is configured to transmit control information to the plurality of infrastructure equipment via the connecting interface to cause the plurality of infrastructure equipment to transmit supplementary positioning reference signals to one or more of the communications devices which are selected by the location server to assist the location server in determining the location of the selected one or more communications devices, characterised in that the controller is configured to determine whether predetermined conditions have been satisfied for causing the supplementary positioning reference signals to be transmitted by the plurality of infrastructure equipment so that the more accurate estimate of the location of the selected one or more communications devices can be generated, wherein the predetermined conditions comprise either determining that the selected communications devices have reported measurements of low quality or determining that the selected communications devices have reported measurements where at least one measurement is missing. a controller configured to determine a location of the communications devices with respect to a location of the infrastructure equipment from observed time differences between receiving the positioning reference signals transmitted by a plurality of the infrastructure equipment, and a connecting interface with the wireless communications network configured to receive reports of the observed time differences from the communications devices and to transmit control information to the plurality of the infrastructure equipment, and the controller is configured to transmit control information to the plurality of infrastructure equipment via the connecting interface to cause the plurality of infrastructure equipment to transmit supplementary positioning reference signals to one or more of the communications devices which are selected by the location server to assist the location server in determining the location of the selected one or more communications devices, characterised in that the controller is configured to determine whether predetermined conditions have been satisfied for causing the supplementary positioning reference signals to be transmitted by the plurality of infrastructure equipment so that the more accurate estimate of the location of the selected one or more communications devices can be generated, wherein the predetermined conditions comprise either determining that the selected communications devices have reported measurements of low quality or determining that the selected communications devices have reported measurements where at least one measurement is missing. <EOS>