How is it that some organizations can maintain nearly error-free performance, despite trying conditions? Within research on such high-reliability organizations, mindful organizing has been offered as a key explanation. It entails interaction patterns among front-line operators that keep them attentive to potential failures—and relies on them having the expertise and autonomy to address any such failures. In this study, we extend the mindful organizing literature, which emphasizes local interactions among operators, by considering the broader institutional context in which it occurs. Through interview, observational, and archival data of a high-reliability explosive demolitions firm in China, we find that external regulators can crucially enhance the mindful organizing of front-line operators as regulators and operators interact around safety rules. Regulators go beyond the interactions emphasized in institutional theory, whereby regulators help operators internalize the content of rules and follow the rules in practice. Rather, regulator interactions also help ensure the salience of rules, which enriches and distributes operator attention throughout the firm. We also find evidence of regulator learning, as interactions with operators help regulators improve rule content and the techniques by which rules remain salient. These findings expand our understanding of mindful organizing and the interactional dynamics of institutions. They also particularly speak to the debate over whether and how rules can enhance safety. Namely, through distinct practices that impact the content and salience of rules, regulators can increase standardization without diminishing operator autonomy.