Leaders are frequently put in the difficult position of repudiating critical questions in front of their followers. To help manage this situation, leaders sometimes express laughter in the hopes that it will “lubricate” their interaction and reduce perceptions that they are aggressive or confrontational with the critical questioner. Ironically, leaders’ laughter may backfire by diminishing their apparent friendliness and approachability in the eyes of the witnessing followers. In this article, we employ an emotional aperture perspective to examine two seemingly contradictory theoretical perspectives regarding the potential impact of laughter on the witnessing followers’ perception of a leader’s warmth and effectiveness. Findings from nine studies across 2,012 adults show that leader laughter—even expressed briefly—bolsters or damages leader effectiveness depending on one important contingency: whether the leader’s laughter is shared by the questioner. Unshared laughter reduces leader effectiveness by undermining leaders’ apparent warmth, while shared laughter increases leader effectiveness by enhancing leaders’ apparent warmth. We discuss implications for the literature on emotion expression, leadership events, and leader perception and influence.