The online catalogue includes :
- Books since 1816
- All the works acquired since 1997
- 75% of the works acquired between 1970 and 1996
- 10% of the works entered before 1970
- Individual collections :
- Charles Bertin Collection (French literature),
- Geoffroy de Beauffort Collection (automobile literature),
- Doize Collection (prehistory),
- Museology collection,
- Collections of Greek and Latin authors
- Antique books up to 1815: Only the new acquisitions of antique works and the "Mons collection" (editions printed in Mons between 1580 and 1815) have been encoded at this time.
- Publications in series (periodicals): All the current periodicals and 50% of the periodicals that have ceased publication.
- Archives and manuscripts
- Handwritten documents by French writers, musicians, scientists, the Bonaparte family, French politicians (15th century - beginning of the 20th century), foreign diplomats, foreign politicians, the army and the navy
- Charles Plisnier collection (under way)
The database is therefore not exhaustive. Consequently, before concluding that a work or a specific document is missing from the Mariemont collections following a fruitless search, it is indispensable to consult the card files accessible in the reading room of the library.