We propose that consideration of affective events theory can enrich our understanding of leader-member exchange (LMX) development. Drawing from previous research, we argue that high-quality LMX relationships progress through three stages: role taking, role making, and role routinization. Affective events theory indicates that emotions are relevant at each of these three stages, although their influence is manifested in different ways and at different levels of analysis. During the initial role-taking stage, leaders’ affective expressions serve as affective events influencing member emotions through the processes of emotional contagion and affective empathy, which determine the progress of further relationship development. Next, during the role-making stage, leaders and members are both sources of affective events, and they may gradually become affectively entrained such that their affective states tend to fluctuate in a common rhythm. This pattern of dyadic-level affect helps to build high-quality LMX relationships over time. Finally, during the role routinization stage, an LMX relationship has been formed but, we argue, could subsequently change based on member emotional responses to the distribution of LMX relationships within a workgroup (LMX differentiation).