Given the literature on the emerging form of Virtual Organization (VO) and the importance of Organizational Memory (OM) in these modem organizations, the contribution of this paper is to identify building blocks of OM in VOs. The exploration of this area has been conducted through a literature review of OM and VOs. Firstly, the paper provides a discussion of the characteristics and organizational elements of VOs found in the literature. Secondly, different OM models presented are discussed. Finally a conceptual model of building blocks of OM in VOs will be presented.Keywords-organizational memory; virtual organizations; net broker memory; project memory I.