Abstract: An international telecommunications network includes a set of international exchanges located in a particular country which connect a national telecommunications network situated in that country with networks situated in other countries. The international network includes a traffic management system in the form of an expert system having a set of knowledge sources. An identifier identifies alarms relating to traffic and a priority arranges the alarms in order of priority. A diagnose diagnoses the cause or causes of the alarms by proposing suspected causes and investigating them in relation to traffic and network data. A resolver proposes remedies for the causes of the alarms by reasoning over each cause in relation to data on traffic associated with the cause, reasoning over each remedy in relation to data on traffic in the neighborhood of the remedy to determine a figure of merit for the remedy and then arranging the remedies in order of merit.