A location management function apparatus in communication network, wherein the location management function apparatus comprises a tracking mode and policy management module configured to: transmit, to a core network, CN, communicating with an user equipment, UE, device in the communication network and a radio access network, RAN, communicating with the user equipment device in the communication network, an instruction to indicate the core network and the radio access network to track the location of the user equipment device to achieve the location of the user equipment device; and the instruction to indicate to the core network and to the radio access network to track the location of the user equipment device comprises three selectable modes i, ii and iii, namely: i) RAN assisted-parallel local tracking, RANPLT, according to which both the RAN and the CN take active part in tracking the location of the UE device, and the location of the user equipment device is tracked concurrently by both the core network and the radio access network, wherein the location of the UE device is estimated by the RAN - wherein result of that is reported to the CN - and also by the CN, so that the CN has two sets of location data for the same UE device, ii) RAN assisted-complemented local tracking, RANCLT, according to which at any one time the location of the user equipment device is tracked by only performing RAN-level tracking or the CN-level tracking, wherein the CN manages the tracking policy both for RAN-level tracking and CN-level tracking and when RAN-level tracking is no longer appropriate, CN-level tracking is resumed and RAN-level tracking is stopped, and vice versa; and iii) CN independent local tracking, CNLT, according to which only the CN performs location tracking and the location of the user equipment device is tracked by the core network communicating with the user equipment device via the radio access network. transmit, to a core network, CN, communicating with an user equipment, UE, device in the communication network and a radio access network, RAN, communicating with the user equipment device in the communication network, an instruction to indicate the core network and the radio access network to track the location of the user equipment device to achieve the location of the user equipment device; and the instruction to indicate to the core network and to the radio access network to track the location of the user equipment device comprises three selectable modes i, ii and iii, namely: i) RAN assisted-parallel local tracking, RANPLT, according to which both the RAN and the CN take active part in tracking the location of the UE device, and the location of the user equipment device is tracked concurrently by both the core network and the radio access network, wherein the location of the UE device is estimated by the RAN - wherein result of that is reported to the CN - and also by the CN, so that the CN has two sets of location data for the same UE device, ii) RAN assisted-complemented local tracking, RANCLT, according to which at any one time the location of the user equipment device is tracked by only performing RAN-level tracking or the CN-level tracking, wherein the CN manages the tracking policy both for RAN-level tracking and CN-level tracking and when RAN-level tracking is no longer appropriate, CN-level tracking is resumed and RAN-level tracking is stopped, and vice versa; and iii) CN independent local tracking, CNLT, according to which only the CN performs location tracking and the location of the user equipment device is tracked by the core network communicating with the user equipment device via the radio access network. i) RAN assisted-parallel local tracking, RANPLT, according to which both the RAN and the CN take active part in tracking the location of the UE device, and the location of the user equipment device is tracked concurrently by both the core network and the radio access network, wherein the location of the UE device is estimated by the RAN - wherein result of that is reported to the CN - and also by the CN, so that the CN has two sets of location data for the same UE device, ii) RAN assisted-complemented local tracking, RANCLT, according to which at any one time the location of the user equipment device is tracked by only performing RAN-level tracking or the CN-level tracking, wherein the CN manages the tracking policy both for RAN-level tracking and CN-level tracking and when RAN-level tracking is no longer appropriate, CN-level tracking is resumed and RAN-level tracking is stopped, and vice versa; and iii) CN independent local tracking, CNLT, according to which only the CN performs location tracking and the location of the user equipment device is tracked by the core network communicating with the user equipment device via the radio access network.