MinSysis a fourth-generation computerized information system developed by Geosystems for the mining and mineral industries. It consists of the MinSys Datorium, the database, together with derived products and associated services. Information sources include the mining industry itself, mining publications and general publications. Subject coverage includes exploration, development, environmental aspects, management, market aspects and government. Indexing is based on Omnisaurus, a multi-level system based on Geosaurus (Geosystems thesaurus), Minsaurus (Geosystems’ list of locations, consisting of organisations, resources and sources), Datasaurus (Geosystems’ data element definitions), and Geosaurus (Geosystems free text controlled terms). MinSys will be made available from computer terminals via telecommunication networks such as Tymnet, Telenet and Euronet.