Ethical leadership has attracted massive attention in the twenty-first century. Yet despite this vast literature, knowledge of ethical leadership suffers from two critical limitations: First, existing conceptualizations conflate ethical leader behaviors with followers' evaluations of leaders' characteristics, values, traits, and followers' cognitions. Second, we know little to nothing regarding the causes and consequences of ethical leadership behaviors as most of the evidence not only confounds concepts, but also precludes causal inferences due to design problems. Thus, we first presenta review of the definitions of ethical leadership that alarmingly reveals a hodgepodge of follower evaluations of leader behaviors, traits, and values. We then address this concept confusion by drawing upon signaling theory in presenting a new conceptualization of ethical leadership behavior (ELB) defined as signaling behavior by the leader (individual) targeted at stakeholders (e.g., an individual follower, group of followers, or clients) comprising the enactment of prosocial values combined with expressions of moral emotions. As such, enacting prosocial values and expressing moral emotions are each necessary for ethical leadership. Next, we review thenomological network of ELB at the individual, dyad, and group levels. We conclude with a discussion of future research directions in testing new theoretical models, including a set of theoretical andmethodological recommendations