Abstract: In recent years the visualization of knowledge has been gaining wider attention: visualization is said to enhance human capabilities for knowledge intense activities such as decision making and strategic thinking. However, this is a recent field and still widely unexplored. Thus far, the advantages of knowledge visualization have been investigated mainly through anecdotal evidence and qualitative studies. In this paper, we propose an experimental approach to further comprehend the role of visualization in fostering knowledge sharing. We plan to compare the elicitation and evaluation processes of groups who are provided (1) with an optimal visual support, (2) with a sub-optimal visual support, and (3) without any visualization. The goal of our research is to apply the experimental approach – widely used in studying GSS (Group Support System) but seldom used in knowledge management – to shed light on the role of visualization for knowledge-intensive tasks in groups. We report first preliminary results of an experiment with 56 MBA students and also outline the limitations of our approach. Keywords: knowledge visualization, collaborative visualization, Group Support Systems, knowledge work, knowledge sharing