Communication of criticism between groups is important to productive societal discourse, but may serve to inflame conflict. The defensive rejection of intergroup, relative to intragroup, criticism (intergroup sensitivity effect ISE) may contribute to such divides. The ISE has been observed in self‐report measures, but such measures are weak and biased predictors of actual (divisive) behavior. We review recent research demonstrating that the ISE does have costly behavioral consequences. We next consider the debate concerning whether the ISE reflects defense of a valued social identity or enforcement of a conversational norm. We therefore review recent evidence for an ISE among individuals lacking identification with the target of the criticism. Third, we examine how the ISE may affect a variety of behaviors relevant to societal divisions, including political reconciliation, environmental sustainability, and vaccination. Lastly, we outline future research that can clarify the underlying mechanisms of the ISE and promote conciliatory intergroup behavior.