The practice of interviewing individuals rather than groups has been based largely upon methodological concerns for preventing contamination of data. The assumptions that (1) the data provided by individuals can, in aggregate, yield social truth; (2) individuals are conscious of social phenomena; and (3) the whole of social reality is equal to the sum of its parts all bear critical examination. The prevailing assumptions about the source of social knowledge, the nature of knowledge itself, and appropriate research methods have been shaped by the philosophy of individualism. Groups are frequently the only appropriate source of social knowledge. Because the results of group interviews are interactive, they will produce meanings that are social products and that probably will be quite different from the prior, socially untested perceptions of any single individual. Group interviews allow the researcher to observe the ways in which interview participants stimulate each other and provide clues to the language, terms, and codes that participants share. Case studies of a program evaluation, a peer group self-analysis, and an assessment of women's perceptions of barriers in job training programs for nontraditional occupations illustrate the role of the group interview in participatory research groups and Freirean study circles where the group factor is significant in and of itself. (MN)