Are Americans more individualistic and less collectivistic than members of other groups? The authors summarize plausible psychological implications of individualism-collectivism (IND-COL), meta-analyze cross-national and within-United States IND-COL differences, and review evidence for effects of IND-COL on self-concept, well-being, cognition, and relationality. European Americans were found to be both more individualistic-valuing personal independence more-and less collectivistic-feeling duty to in-groups less-than others. However, European Americans were not more individualistic than African Americans, or Latinos, and not less collectivistic than Japanese or Koreans. Among Asians, only Chinese showed large effects, being both less individualistic and more collectivistic. Moderate IND-COL effects were found on self-concept and relationality, and large effects were found on attribution and cognitive style.