An information management system and method reduces the amount of data generated and transmitted for analysis and observation over a first network. An information management sub-system, includes a manager that analyzes or observes data, which is collected by multiple agents connected therewith through the first network. A sub-manager is connected with the agents via a second network, and manages data for the targets of management (such as, various kinds of information data collected by the agents, programs for collecting/analyzing the collected data, and data of analysis results thereof) in a storage, which is also connected with the second network, and which is used commonly between the sub-manager and the agents.