About 100 publications each year use the concepts of individualism and collectivism in discussing a study of social behavior. The colloquium will discuss the definition of these concepts, their antecedents and consequences, and will review some key findings. Collectivism is associated with greater emphasis on the situation. In all cultures there are personality types that show a predisposition that corresponds to individualism (idiocentrics) and collectivism (allocentrism), but the proportions of allocentrics are different in different cultures. Studies that examine the interaction of the situation and predisposition will be reviewed. There are also differences in attributions, goal setting, motivation, social exchanges, ease of entering new groups, recreation, communication and morality that have been found to be associated with the two cultural patterns.