The Belgian Science Policy Office, which includes the Royal Library of Belgium also known as KBR, has launched an institutional Open Access Repository for Federal Organisations (ORFEO). KBR has been involved at two levels in this project: by the integration of the publications from its researchers and as a partner for the development of the repository. In the context of the latter, an analysis was conducted in order to consider the future of ORFEO and its possible integration in KBR’s collections. This analysis included a reflection about how a national library, whose mission includes legal deposit, can play a role regarding grey literature. This article presents the initiatives for Open Access at a federal level, the particularities and the current situation of the Belgian legal deposit and how grey literature can be taken into account. Finally, the three analysed approaches to take over ORFEO are detailed.