Darker aspect of personality (e.g., narcissism, psychopathy) have been shown to be associated with a wide range of workplace outcomes. However, relatively little is known about the psychological mechanisms that may explain these associations. The purpose of the present study was to examine whether the associations that dark personality features had with workplace outcomes were explained, at least in part, by difficulties in self-functioning (i.e., identity, self-direction) and interpersonal functioning (i.e., empathy, intimacy) in an Israeli community sample. Our results revealed that difficulties in self-functioning often mediated the associations that dark personality features had with workplace outcomes. More specifically, difficulties with self-direction mediated the associations that psychopathy, sadism, and spitefulness had with task performance and contextual performance, whereas difficulties with identity mediated the associations that Machiavellianism, psychopathy, sadism, and spitefulness had with counter-productive work behaviors. Although Machiavellianism, psychopathy, sadism, and spitefulness were strongly associated with difficulties with empathy and intimacy, these difficulties with interpersonal functioning were not associated with workplace outcomes. Discussion focuses on the role that difficulties in self-functioning and identity may play in the connections between dark personality features and workplace outcomes.