People often cling to beliefs even in the face of disconfirming evidence and interpret ambiguous information in a manner that bolsters strongly held attitudes. The authors tested a motivational account suggesting that these defensive reactions would be ameliorated by an affirmation of an alternative source of self-worth. Consistent with this interpretation, participants were more persuaded by evidence impugning their views toward capital punishment when they were self-affirmed than when they were not (Studies 1 and 2). Affirmed participants also proved more critical of an advocate whose arguments confirmed their views on abortion and less confident in their own attitudes regarding that issue than did unaffirmed participants (Study 3). Results suggest that assimilation bias and resistance to persuasion are mediated, in part, by identity-maintenance motivations.