A plurality of general-purpose diagnosis procedure is prepared. Each general-purpose diagnosis procedure is a general-purpose diagnosis procedure associated with any of a plurality of rules and defined using one or a plurality of component types. Each rule indicates association between one or more condition events and a conclusion event. A management system, on the basis of one or more object rules with which one or more condition events related to one or more generated events are associated, identifies one or more cause candidates, and identifies the general-purpose diagnosis procedure associated with an object rule as a basis for the selected cause candidate among the one or more cause candidates. The management system, on the basis of the identified general-purpose diagnosis procedure and configuration management information which is information about the configuration of a plurality of management object components, generates an expanded diagnosis procedure which is a diagnosis procedure implemented with respect to one or more management object components and which is for identifying a more concrete cause of the selected cause candidate or for updating the certitude of the selected cause candidate.