This audit aims to establish how well departments are using their internal audit resources. Each public sector entity is required to establish, maintain and resource an internal audit function that is independent of management. This internal audit function is overseen by the audit committee and encompasses both internal resources and the activities of the agency’s externally appointed internal auditors. Over several years, numerous performance audits have questioned the effectiveness of agencies’ use of internal audit resources. Recurring issues relate to the adequacy of internal audit resources—their capacity and capability—and to the whether the way they are used within the risk and control environments of each entity maximises their value and impact. This audit will examine the resourcing and deployment of internal audit effort within each department, and its operational effectiveness as one ‘line of defence’ within departmental assurance frameworks.