The topic of dark side personality at work has received considerable research attention over the past decade, and both qualitative and quantitative reviews of this field have already been published. To show the relevance of dark personality in the work context, existing reviews have typically focused on systematically discussing the different criteria that have been linked to dark traits (e.g., job performance, work attitudes, leadership emergence, etc.). In contrast, and complementing this earlier work, the current review paper summarizes the available literature on this topic by structuring it in terms of the nature of the relationships studied rather than in terms of the types of outcome variables. Doing so, the focus shifts from "What are the outcomes of dark traits?" to "How are dark traits related to work outcomes?" Scrutinizing the nature of these relationships, we specifically focus on four types of effects (i.e., nonlinear, interactive, differential, and reciprocal) that highlight the complexity of how dark side traits operate in the work context. Structured this way, this review first provides a conceptual underpinning of each of these complex effects, followed by a summary of the empirical literature published over the past 10 years. To conclude, we present an integration of this field, provide suggestions for future research, and highlight concrete assessment challenges.