An account of discourse and bureaucratic process must of necessity confront the question of linkages between the macrostructures of a social order and the microstructures of any communicative act. Focusing on theoretical and analytic issues, this paper discusses how the concept of index can be used to provide a capacious yet coherent account of communicative context, one which can be integrated into the more general characterization of social relations provided by the study of institutional ideologies. The argument is illustrated with materials taken from educational studies. It concentrates on ability grouping and prescriptivism, analyzing both as ideologies which engender a structuring practice with demonstrable effects on the organization of face‐to‐face communication as well as on the general form of bureaucratic institutions.