ORBi (Open Repository and Bibliography) has been conceived to respond to a dual objective : (1) to collect references for the totality of scientific publications of the University of Liège (backdated to 2002) ; (2) to allow, within the limits possible, open and free access to all articles published by ULg members (backdated to 2002), following the Immediate-Deposit/Optional-Access (ID/OA) principle.