National symbols pervade most contemporary societies, and public policies encourage the displays of these symbols, yet little research has considered the psychological and social effects of exposure to national symbols. The current review integrates theorizing across social science disciplines and proposes that national symbols are not passive fixtures of people's environment, but instead may yield significant psychological and social effects. Empirically supported intraindividual consequences include enhanced national identification and the promotion of group unity at an unconscious level. National symbols may also have important implications for intergroup relations due to their relation to heightened national identification and potential to automatically activate concepts associated with nationhood. The factors that contribute to differential responses to national symbols and profitable avenues of future research are discussed.