In his famous 1982 address as a president of the American Sociological Association, Erving Goffman returns to the relation between the interaction order and social structures, which he defines as a 'loose coupling'. This paper elaborates on this intriguing but partially disappointing response, and proposes to complement it by analyzing the role of institutions. First, individual interactions, shaped by macrostructural patterns while never reducible to them, do not matter always and everywhere in terms of impact on social structures. They do under specific conditions and settings. Second, institutions can be regarded, in a Durkheimian perspective, as "crystallized social forms," which make social norms and patterns of collective life appear concretely in the phenomenal world, expressing and reproducing the social order. Third, when institutions proceed in an individualizing and atomizing way, interactions matter; they become a means for assigning identities and statuses, and for regulating individual behaviors. Beyond a "loose coupling" between the interaction order and the social order, institutions can then be viewed as forging a strong link between these two levels. To illustrate these propositions, this paper focuses on "people-processing encounters" during which, and thanks to which, "even the most disadvantaged categories continue to cooperate," to quote again Goffman's terms; namely on interactions between welfare officials and their clients