Proportions, that is, relative numbers of socially and culturally different people in a group, are seen as critical in shaping interaction dinamics, and four group types are identified in the basis of varying proportional compositions. "Skewed" groups contain a large preponderance of one type (the numerical "dominants") over another (the rare "tokens"). A framework is developed for conceptualizing the processes that occur between dominants and tokens. Three perceptual phenomena are associated with tokens: visibility (tokens capture a disproportionate awareness share), polarization (differences between tokens and dominants are exaggerated), and assimilation (tokens' attributes are distorted to fit preexisting generalizations about their social type). Visibility generates performance pressures; polarization leads dominants to heighten their group boundaries; and assimilation leads to the tokens' role entrapment. Illustrations are drawn from a field study in a large industrial corporation. Concepts are extended to tokens of all kinds, and research issues are identified.