OPAC SBN ( where OPAC stands for "on line public access catalogue") allows customers to enter with formality of friendly search to the collective catalogue of libraries that take part in the National Library Service.

The National Library Service (SBN) is the Italian libraries network promoted by the General Direction for Library Heritage and Cultural Institutes in cooperation with the Regions and the Universities, with the coordination of the Central Institute for the Union Catalogue of Italian Libraries and for Bibliographic Information (ICCU). Participating to the SBN are at now about 4900 state, university, academies, local bodies, and public and private institutions libraries, operating in different sectors.

The collective SBN catalogue (SBN Index) contains:

The data base of the OPAC SBN updates weekly.

Through the OPAC SBN it is possible to:
Searches on the whole SBN catalogue are of three types:
To search single document typologies it is possible to access, by using specific channels, particular sections of the SBN Catalogue (thematic or specialized searches) relative to:
For all types of search, in the case when the gotten result is too wide, it is possible to refine it adding further elements of selection.

The 'Other Catalogues' module permits to make, with the same interface, bibliographical searches in other Italian and foreign catalogues conforming to the international standard Z39.50. The module permits to access some predefined catalogues ( "Multicatalog search"), searchable also simultaneously. With the function "Custom search" the user can configure and search other Z39.50 catalogues of which he knows the access parameters.

The Services module allows: