We may call them “site inspections”, but it’s not the site that’s being inspected when a regulator visits; it’s the Principal Investigator. Though a PI typically delegates study tasks to other staff members, he or she remains solely responsible for the conduct of the study. In fact, the ICH E6(R2) addendum adds two new sections to the international guidance that emphasize PI supervision.That’s what makes the Delegation of Authority (DoA) log so important and why regulatory inspectors care about it so much. A DoA log serves as evidence that a PI has assigned study tasks only to those staff members with the education, training, and experience to carry them out. If delegates are unqualified to perform their tasks, subject safety could be at risk and it’s highly likely that the study data would be unusable.