Purpose: While knowledge management has been shown to be a strategic source of competitive advantage, processes designed to enhance the productivity of knowledge do not, however, equally contribute to the organization's capabilities. Consequently, this research aims to focus on the relationship between each mode of the knowledge management process and multiple sources of competitive advantage. Design/methodology/approach: This research, using questionnaire data collected from the entire population of a pharmaceutical company's head office in Japan, investigates how different perceptions and behaviors related to knowledge management affect the perceived contribution of certain types of organizational knowledge acting as sources of competitive advantage. Findings: The study finds that the perceived importance of knowledge management activities, especially combination, appears as an important source of competitive advantage related to technical knowledge, and more time spent on knowledge management tasks, in particular socialization, contributes to a competitive advantage related to affective knowledge. Further analysis involves a taxonomy of employees based on their perceived importance of, and the time they spend on, knowledge management activities. Research limitations/implications: This paper focuses on the entire population of a single firm, and for that reason, further research with other companies in different industries is necessary. Practical implications: There is evidence suggesting that knowledge management strategies should be tailored to fit the discriminate beliefs and actions of each group of workers, identified based on their level of congruence between their espoused theories and theories-in-use related to knowledge management. Originality/value: The taxonomy of workers introduced in the paper emphasizes the fact that the workforce is not a uniform body and therefore that intrinsic differences need to be taken into account to maximize the efficiency of knowledge management. (Contains 7 figures and 4 tables.)