Quite likely, there’s a psychopath on our office floor and we don’t even know it. When we think of psychopaths, we usually think of killers from TV series. But in the workplace, when we need to rely on and to trust, whom we work with toward common goals, even when obstacles stand in the way, this unfavorable personality constellation can jeopardize harmonious working life. Psychopaths are known for their counterproductive work behavior (CWB). Psychopathic individuals represent unethical corporate values (Valentine et al., 2018) and make unethical decisions (Watson et al., 2017). They tend to manipulate others in the workplace in order to gain recognition for their work performance (e.g., Jonason et al., 2012). Their deviant behavior in the workplace is directed not only against the organization (e.g., sabotage), but also against their colleagues (e.g., theft; e.g., Schilbach et al., 2020). Further, psychopaths tend to perform poorly on the job (e.g., Babiak et al., 2010; McLarty & Holt, 2019). They cut corners at work (Jonason & O’Connor, 2017), spend their working hours cyberloafing (Lowe-Calverley & Grieve, 2017), impair organizational collaboration (e.g., Pan et al., 2018), and show a reduced organizational citizenship behavior (OCB; McLarty & Holt, 2019). In general, the work engagement of mean and disinhibited employees seems to be very limited (Sutton et al., 2020). These issues may even be exacerbated the higher one moves up to the hierarchical level within an organization. The higher the hierarchical level inside the organization, the more often we find psychopaths (Spencer & Byrne, 2016). This has serious consequences. Psychopathic supervisors are prone to self-serving behavior (e.g., Barelds et al., 2018) and abusive supervision (e.g., Mathieu & Babiak, 2016; Sutton et al., 2020). Almost everyone working under a psychopathic supervisor has experienced or witnessed unfavorable treatments (bullying) at work (Boddy, 2011). The consequences of psychopathic supervisors include lower job satisfaction, lower organizational commitment, more burnout, and higher turnover intentions among employees (e.g., Mathieu & Babiak, 2016; Sanecka, 2013; Sutton et al., 2020; Tokarev et al., 2017). Regardless of these well convincing findings and their conceptual background, the dominant meta-analysis on the topic presents a completely different pattern: Psychopathy has no noteworthy effect on job performance (r = -.08), nor on CWB (r = .06; O’Boyle et al., 2012). This discrepancy can be explained by the fact that O’Boyle et al. (2012) mostly included studies from between 1950 and 1990, which were based on an outdated psychopathy construct (e.g., Minnesota Multiphasic Personality Inventory; Hathaway & McKinley, 1943) that differs greatly from today’s theorizing (e.g., Hare & Neumann, 2008) or the diagnosis of psychopathy as a personality disorder (e.g., the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, DSM-5; American Psychiatric Association, 2013). As the number of studies dealing with psychopathy and its effects on organizations has steadily increased since the meta-analysis by O’Boyle et al. (2012), we want to establish a new meta-analysis. Recently published meta-analyses on Honest-Humility (a personality domain similar to the inversion of the psychopathy construct but not equivalent to it; Muris et al., 2017) show, for example, that Honest-Humility has a strong negative effect on CWB (r = -.36; Lee et al., 2019) and on workplace deviance (r = -.35; Pletzer et al., 2020). Applied to psychopathy, this suggests that, contrary to the meta-analysis of O’Boyle et al. (2012), psychopathy may be positively linked to CWB. In Honest-Humility, the findings on OCB and task performance were not as pronounced as in CWB (Lee et al., 2019), but a tendency can be deduced that psychopathy may be negatively linked to both. In our meta-analysis, we include only studies based on the current understanding of psychopathy (e.g., American Psychiatric Association, 2013). We want to shed light on the impact of psychopathy in the workplace in a comprehensive way. Therefore, we focus on the effects on CWB, OCB, and task performance. In addition, moderation effects have so far gone unnoticed. Are there differences between primary and secondary psychopathy, in which primary psychopathy has adaptive and secondary maladaptive effects on the workplace? Does it make a difference whether the psychopathic individual is a supervisor or an employee? Is there a difference in the relationships between psychopathy and individual CWB/OCB or organizational CWB/OCB? We also want to examine all these moderators in the meta-analysis, which have not been considered so far.