We are interested in the bases of social emotions such as compassion and hostility. Our analysis centers on social explanations, or people’s answers to the question: Why does the target behave that way or experience those outcomes? Below, we review classic approaches to social explanation and then review work linking explanations to emotions. Finally, we focus on work from our lab that connects explanations to prosocial emotions and intergroup attitudes, including compassion for the disadvantaged and reduced vengefulness toward the violent. A crucial contribution of our work is to illuminate complex connections between explanations and emotions: A given explanation has different socio-emotional implications depending on the explainer’s motives. Finally, we review our work suggesting that individuals have social explanatory styles, and that particular styles are predictive of dispositional compassion. A key implication of our work is that social explanations are another basis of prosociality, in addition to factors such as empathy and moral principles.