Over the past two decades, there has been a significant shift in how dehumanization is conceptualized and studied. This shift has broadened the construct from the blatant denial of humanness to groups to include more subtle dehumanization within people’s interpersonal relationships. In this article, we focus on conceptual and empirical advances in the study of dehumanization in interpersonal relationships, with a particular focus on dehumanizing behaviors. In the first section, we describe the concept of interpersonal dehumanization. In the second section, we review social cognitive and behavioral research into interpersonal dehumanization. Within this section, we place special emphasis on the conceptualization and measurement of dehumanizing behaviors. We then propose a conceptual model of interpersonal dehumanization to guide future research. While doing so, we provide a novel review and integration of cutting-edge research on interpersonal dehumanization.