A growing body of research shows that rudeness negatively affects individual functioning and performance. Considerably less is known about how rudeness affects team processes and outcomes. In a series of five studies aimed at extending theories of the social-cognitive implications of rudeness to the team level, we show that rudeness is detrimental to team functioning. Using an experimental design, Study 1 shows that teams encountering rudeness perform worse than other teams. Study 2, a medical simulation study, explains this effect by showing that medical teams exposed to rudeness are less likely than other teams to share information and workload and, in turn, execute a variety of medical procedures less well. Studies 3a and 3b highlight the mediating role played by social value orientation (SVO), demonstrating that rudeness elicits these effects by diminishing members' SVO (i.e., making team members less prosocial and more pro-self). In turn, Study 4 shows that rudeness-diminished SVO explains reduced information sharing in teams. Finally, Study 5, a laboratory study, tests a full serial mediation model, demonstrating that rudeness decreases team members' SVO, which in turn reduces team information sharing and, as a result, encumbers team performance. Overall, these findings show that rudeness can have severe implications for team functioning and may even have life-threatening consequences.