This chapter focuses on the relationship between representations of work (rules, procedures, models, specifications, plans) and work as a situated practice, performed by real people in always unique contexts. Empirically, it is organized around two main examples, the first one being a discussion of the compartmentalization of safety seen in shipping and the railway sector. It shows how safety, as an object of management, has become decoupled from practice, and how current discourses about safety disempower practitioners and subordinate their perspectives to more "theoretical" positions. The second is based on a study of control room operators in a space research operations setting. Here safety in the sense of avoiding harm to people is not the main concern; rather it is the reliability and robustness of an experiment on the International Space Station that is at stake. This example serves as a starting point for discussing how the research and theory on industrial safety should address the different temporalities of different work situations. It also helps to discuss the role of rules and procedures to support safety, reliability and resilience within the field of safety science. Finally, some propositions about the relationship between situated practice and the management of safety are provided: how invisible aspects of situated work might be important for safety yet hard to manage, how procedures and rules might be integrated parts of situated work as much as representations of it and how different temporalities of work situations should be included in the theorizing of safety and resilience.