Personality traits have a strong genetic foundation, are highly stable over time, and predict important societal outcomes, including health and occupational success. In his Perspective, Robins discusses Terracciano et al.'s finding that cultures differ somewhat in aggregate personality levels but those differences are not accurately reflected in stereotypes about national character. Robins discusses reasons why national stereotypes are inaccurate, as well as broader issues concerning individual and cultural sources of variation in personality.