While Knowledge Management (KM) has been shown to be a strategic source of competitive advantage (CA), processes designed at enhancing the productivity of knowledge do not however equally contribute to the organization’s capabilities. Consequently, this research, using data collected from the entire population of a firm’s personnel in Japan, focuses on the relationship between each mode of the KM process and multiple CAs, and investigates how different perceptions and behaviors on KM affect those CAs. This research-in-progress paper reports preliminary results showing that the perceived importance of KM activities appears as an important source of ‘technical competitive advantage’, and that more time spent on KM activities contributes to an ‘affective competitive advantage’. Further analysis involves a taxonomy of employees based on their perceived importance of and the time they spend on KM. The goal of this research is to identify, among sub-groups by department or function, specific KM processes that can durably increase the firm’s competitiveness, and to examine eventually whether KM behaviors have a uniform effect on CA across national borders within the same company.