In every organization, individual members have the potential to speak up about important issues, but a growing body of research suggests that they often remain silent instead, out of fear of negative personal and professional consequences. In this chapter, we draw on research from disciplines ranging from evolutionary psychology to neuroscience, sociology, and anthropology to unpack fear as a discrete emotion and to elucidate its effects on workplace silence. In doing so, we move beyond prior descriptions and categorizations of what employees fear to present a deeper understanding of the nature of fear experiences, where such fears originate, and the different types of employee silence they motivate. Our aim is to introduce new directions for future research on silence as well as to encourage further attention to the powerful and pervasive role of fear across numerous areas of theory and research on organizational behavior. “If any human emotion is as old as our species it must, surely, be fear, and the end of its hold on us is not in sight.” (Scruton, 1986: 7)