As the awareness of the importance of managing organizational knowledge grows, the issue of how to build information and communication technology (ITC)-based systems to support knowledge management activities, i.e., knowledge management support systems (KMSSs), has been raised. However, knowledge and its manipulating activities, by their very nature, are sociotechnical phenomena in which social and technical factors interweave the ways in which people work. Therefore, the success of any knowledge management support system depends not only on its technical excellence, but also on its compatibility with the social and cultural fabric of the firm in which it is embedded. In this exploratory work it is argued that actor-network theory (ANT) provides theoretical foundations for the KMSS development process. In order to apply ANT in the context of knowledge management, several concepts are introduced, namely, Business Thing, Knowledge Thing and Knowledge Actor, together with a Role ontology.