This paper describes the results of a study that examines how formal analysis is actually used in practice in three different organizations. Four main groups of purposes for formal analysis--information, communication, direction and control, and symbolic purposes--are identified and related to the nature of the social and hierarchical relationships between those who initiate analysis, those who do it, and those who receive it. It is concluded that, far from being antithetical as often assumed, formal analysis and social interaction are inextricably linked in organizational decision making and that different structural configurations may generate different patterns of use of analysis.