The Division of Internal Audit follows standards as set forth by the Institute of Internal Auditors, The Professional Practices Framework (PPF). The PPF consists of three categories of guidance: Standards and Ethics, Practice Advisories, and Development and Practice Aids. The first category consists of mandatory core materials: the Code of Ethics and the Standards for the Professional Practice of Internal Auditing. The Standards are the criteria by which the operations of an internal audit department are evaluated and measured. They are intended to represent the practice of internal auditing. Guidance in the second category, the Practice Advisories are strongly recommended and endorsed by the Institute. Although not mandatory, Practice advisories represent best practices endorsed by the Institute as ways to implement the Standards. The third category of guidance includes a variety of materials that are developed and/or endorsed by the Institute. This category includes research studies, books, seminars, conferences, and other products and services to the professional practice of internal auditing that do not meet the criteria for inclusion in Mandatory Guidance or Practice Advisories. Compliance with the concepts detailed in the Mandatory Guidance is essential before the responsibilities of internal auditors can be met.