Abstract. The aim of this paper is to grasp the ethical dilemmas that arise into organizational knowledge and the importance of trust for diminishing these dilemmas. Therefore, it focuses three key issues: knowledge management (concept; and, schools of thought); knowledge flowing models versus ethics (mental models; the Socialization, Externalization, Combination, Internalization (SECI) model; and, Fiske's relational model); and finally, the importance of trust as a possible answer. Plus, this paper suggests that the previous models only focus knowledge as continuum process and the result of this process omits ethical and moral dilemmas (obligation to share, personal property, personal worth, autonomy, dignity, privacy, etc.). These ethical dilemmas clearly weaken a knowledge management project, and how trust is a reliable answer. The absence of empirical work should be considered a limitation of this paper; however, does not diminish the importance for this debate.