A method for assigning a location area to a mobile device in fallback from a first radio access network to a second radio access network, the first radio access network including at least a base station node, the method comprising: whenever the base station node receives signals incorporating a location area code, LAC, and further identifying data corresponding to the second radio access network, providing a respective first counter for each unique location area identified in said signals, said location area having a corresponding location area code, wherein the further identifying data comprises at least one of a Mobile Country Code and a Mobile Network Code; characterised by: for each received signal, checking the respective first counter for the location area code and conditionally incrementing the first counter such that if the first counter is below a predefined threshold the counter is incremented; if the first counter is equal to the threshold, incrementing a second counter for corresponding unique combination of location area code and further identifying data; reporting, at predetermined intervals, the counts from second counters to the first radio access network; and an operator using the counts from second counters to predict the location area to use within the operator's own network when the mobile device falls back from the first radio access network to the second radio access network. whenever the base station node receives signals incorporating a location area code, LAC, and further identifying data corresponding to the second radio access network, providing a respective first counter for each unique location area identified in said signals, said location area having a corresponding location area code, wherein the further identifying data comprises at least one of a Mobile Country Code and a Mobile Network Code; characterised by: for each received signal, checking the respective first counter for the location area code and conditionally incrementing the first counter such that if the first counter is below a predefined threshold the counter is incremented; if the first counter is equal to the threshold, incrementing a second counter for corresponding unique combination of location area code and further identifying data; reporting, at predetermined intervals, the counts from second counters to the first radio access network; and an operator using the counts from second counters to predict the location area to use within the operator's own network when the mobile device falls back from the first radio access network to the second radio access network. for each received signal, checking the respective first counter for the location area code and conditionally incrementing the first counter such that if the first counter is below a predefined threshold the counter is incremented; if the first counter is equal to the threshold, incrementing a second counter for corresponding unique combination of location area code and further identifying data; reporting, at predetermined intervals, the counts from second counters to the first radio access network; and an operator using the counts from second counters to predict the location area to use within the operator's own network when the mobile device falls back from the first radio access network to the second radio access network.