Based on a sociological stance, this paper seeks to reflect on the formal and informal dimensions in the analysis of organizations. It focuses specifically on the organizational structure and its relationship with the social processes that shape the organizational dynamics. To fulfill this aim, this reflection discusses the concept of organizational structure as a pivotal element of the formal dimension of organizations, as well as its relevance as a key element of organizations. These elements make it unavoidable in any sociological analysis of organizations, whatever their nature, even in studies whose object is more directed to social dynamics and interactions. The results of this article allow concluding that there is heuristicity and, even, an indispensability to establish and analyze the relationship between the formal structure as a framework for the practices that take place in the organization and the existing concrete practices, which is often not simple to operationalize.