Machiavellianism is a popular construct in research on ethics and organizational behavior. This research has demonstrated that Machiavellianism predicts a host of counterproductive, deviant, and unethical behaviors. However, individuals high in Machiavellianism also adapt to their organizational surroundings, engaging in unethical behavior only in certain situations. Nevertheless, the utility of Machiavellianism has been questioned. Meta-analyses have demonstrated that psychopathy out-predicts Machiavellianism for most antisocial outcomes. Thus, many researchers assume Machiavellianism is a derivative and redundant construct. However, researchers examining the utility of Machiavellianism may be asking the wrong question about how Machiavellianism is unique. In our review, we find it less informative to ask about what antisocial behaviors Machiavellianism predicts. Instead, we find it more informative to ask when Machiavellianism predicts antisocial behaviors. Drawing on Field Theory and Trait Activation Theory, we argue that Machiavellianism is a trait that is associated with person × environment interactions. Their adaptive nature is made possible through the presence of impulse control and environmental sensitivity to punishment, two characteristics that individuals high in psychopathy lack. Consequently, individuals high in Machiavellianism constrain their antisocial behavior to environments when the benefits outweigh the costs. Thus, environmental context, especially the risk of external punishment, moderates Machiavellian misbehavior more than it does for those high in psychopathy. These behavioral constraints align with Lewin’s argument that behavior is a function of the person, environment, and interaction between the two. From this discussion, we arrive at recommendations pertaining to the future of Machiavellianism research in organizational and other applied settings.