The authors examined how gender stereotypes affect negotiation performance. Men outperformed women when the negotiation was perceived as diagnostic of ability (Experiment 1) or the negotiation was linked to gender-specific traits (Experiment 2), suggesting the threat of negative stereotype confirmation hurt women's performance relative to men. The authors hypothesized that men and women confirm gender stereotypes when they are activated implicitly, but when stereotypes are explicitly activated, people exhibit stereotype reactance, or the tendency to behave in a manner inconsistent with a stereotype. Experiment 3 confirmed this hypothesis. In Experiment 4, the authors examined the cognitive processes involved in stereotype reactance and the conditions under which cooperative behaviors between men and women can be promoted at the bargaining table (by activating a shared identity that transcends gender).