Abstract: A method in conjunction with updating one or more HLR-databases included in a GSM-type mobile telephone system. Updating of an HLR is requested by sending a so-called Reset-message, which identifies the HLR-database concerned, to a number of VLR-databases. The losses in process capacity of the VLR-bases will be relatively small, because of the following: The time points at which Reset-messages and the time points at which radio contacts were made with different mobile stations are registered in each VLR. For each radio contact made between a VLR and a mobile station, a search is made in VLR to ascertain whether the mobile station belongs to an HLR which has been requested updating. If such is the case, the time point of the preceding radio contact between VLR and the mobile station is compared in VLR with the time point at which the Reset-message was received, wherein HLR is updated with data from VLR when the preceding radio contact occurred before the Reset-message was received.