Member states are represented by their national centres which are responsible for the collection of grey literature published in the given country, and the database is available through them. The SIGLE database contained 685 thousand bibliographic records at the end of 2000. Economy and natural sciences have the most records. From the genre point of view, research and technical reports, PhD dissertations, theses, conference papers, and materials for discussions constitute the database. Half of the records come from the London centre. The database has the national database of German grey literature (FTN) under its umbrella, too. National centres provide input records with a standardised structure. Each record contains the bibliographic data of the original document: title (in English and/or the original language), authorship, research institute or academic institution, date of publication, type of document, pages, language of the document. The system uses alphanumeric subject codes for subject processing. The database can be accessed online through Blaise or STN International from the EU member states.

The documents that are included in the database are available through the national centres as well. In Hungary the Central Library of the Budapest Technical University is the national centre, but they submit records of technical dissertations defended there only.