COBISS.SI represents an organisational model of joining Slovenian libraries into a uniform library information system with shared cataloguing, the COBIB shared bibliographic database, i.e. union catalogue, and local bibliographic databases of participating libraries, the COLIB database on libraries, the CONOR authority database, and with a number of other functions of the so-called virtual library. Functioning of the system is preconditioned by:Standardised and shared processing of library materials as well as a uniform management of catalogues and bibliographies;Adequately skilled cataloguers;Linking of libraries via computer and communications network.