This chapter explores the relevance of the economics and sociology of conventions (EC/SC or convention theory) as a theoretical framework to study cooperatives. Three main arguments are developed. First, cooperative institutional characteristics make them more transparent, egalitarian, and reflexive than capitalist firms which is likely to produce more situation of disputes and uncertainty that can be analyzed through EC/SC. Second, the economies of worth framework allows authors to explore the microfoundations of individual and organizational responses to institutional pluralism. To demonstrate this point, empirical articles on cooperatives are reviewed, and comparisons and perspectives for future researches are suggested. Third, EC/SC brings light to one of the crucial questions in the literature on cooperatives: their level of autonomy from capitalist institutions. To address this question, the empirical literature on cooperatives uses EC/SC in an effort to characterize the conditions under which some cooperatives can develop autonomy and criticism of the capitalist institutions.