The Director for Conservation and the Heritage and the Assistant Director are responsible for the BNU’s early collections, i.e. all the collections kept in the Reserve Stacks (Egyptology, numismatic, manuscript and incunabula collections, etc), old printed documents (printed before 1920), and iconographic documents.
Before the launch of the 'New BNU' architectural project, the library had three strong rooms called Reserve Stacks where the most precious and most fragile documents were kept. Two of these Stacks - for manuscripts and incunabula - were in the building on the Place de la République, and were removed at the end of December 2010 and in early January 2011 to a place newly fitted out to house them, in the Rue Joffre building. The BNU currently has more than 6 900 manuscripts (ancient and modern) and 2 022 incunabula.
Supervised by the Assistant Director for Conservation and the Heritage, the BNU's Restoration Workshop works to protect and conserve the institution's heritage items. Apart from binding work (restoration, creation, etc), the workshop is capable of handling every type of medium and material (paper, wood, leather, etc) used for manuscripts and printed matter, whether the documents are bound or otherwise.
The Iconography and Cartography Department is in charge of the BNU's collections of fixed and animated images. These collections contain nearly 200 000 documents, including about 50 000 maps and plans. The Department is responsible for handling printers' statutory deposits of maps of the region, posters, leaflets and graphic documents printed in Alsace.
The Digital Library Department is responsible for both photographic and digital reproduction of documents, particularly to meet requests from outside the BNU, and guiding the operational aspect of the BNU's digitisation programmes.
The Equipment Department is responsible for protecting and labelling the BNU's new acquisitions, the upkeep and communication of the heritage collections, and the physical presentation of the collections. It is heavily involved in preparing collections to be available for free access, access in the New BNU, and in a campaign for reconditioning the collections of periodicals.