Audits of site PSM systems are commonly conducted to help ensure compliance with regulatory and corporate requirements, to help identify continuous improvement opportunities for site PSM programs, and to serve as leading indicators of PSM performance. Operational Discipline is the ability of an organization to rigorously execute PSM system requirements correctly every time in order to avoid injuries and incidents and to achieve high levels of PSM performance. Operational Discipline should therefore be an important focus in PSM audits, although this is often difficult and there is only limited guidance on effective auditing approaches. The purpose of this paper is to discuss how Operational Discipline can be evaluated to help improve the quality and benefits of PSM audits.