A meta-analysis reported in this article compared the effects of ontological and utilitarian measures of individualism and collectivism on the findings of published research. Ontological differences in individualism and collectivism concern the degree to which either individuals or collectivities are interpreted as the primary entities comprising social reality. Reflecting these differences are measures that include subjects such as the degree of permanence and sense of collective obligation associated with interpersonal, group, or community relationships. Utilitarian distinctions in individualism and collectivism involve beliefs that either individuals or collectivities are instrumental in the pursuit of valued outcomes. Related measures include items concerning the attractiveness or consequences of working alone versus working in a group. Results of the meta-analysis indicated that ontological and utilitarian measures have produced differing findings in several notable instances, with utilitarian measures producing larger effects.