DELNET has been actively engaged with the compilation of various Union Catalogues of the resources available in member-libraries.It has already created the Union Catalogue of Books,Union List of Current Periodicals, Union Catalogue of Periodicals,CD-ROM Database,Database of Indian Specialists, Database of Periodical Articles, Union List of Video Recordings, Urdu Manuscripts' Database, Database of Theses and Dissertations, sample databases of language publications using GIST technology and several other databases. The data is being updated in these databases and is growing rapidly. All the DELNET databases have been resident on DELSIS, an in-house software developed on BASISPlus, an RDBMS, the product of Information Dimensions Inc. of USA which has been provided to DELNET courtesy National Informatics Centre, New Delhi.