In this article I use institutional theory to illustrate the process of identity formation and reproduction in the context of a male-dominated work environment. Based on a case study of an underground colliery in Nova Scotia, Canada, I will illustrate the functioning of powerful institutions in two distinct senses. First, social obligations rooted in a ‘logic of appropriateness’ (March and Olsen, 1989) dictated appropriate behaviours for miners in their roles as underground miners and patriarchs. Second, internalized understandings of reality rooted in a ‘logic of orthodoxy’ (Scott, 1995) formed a set of constitutive rules to which miners adhered because it was inconceivable to do otherwise. I use a microinstitutional perspective (Zucker, 1991) that highlights the constraints embedded in many work contexts that serve to tacitly yet powerfully regularize behaviours in problematic ways. Social and historical conditions are therefore incorporated into this analysis as constitutive forces that are a product of human action. This manner of theorizing gender is consistent with Connell’s (1987) ‘theory of practice’ that seeks to understand social structure by focusing on what people actually do, the way human agency shapes history, and how practice itself is necessary for institutions to maintain their hegemony and resist change.