This research brief compiles findings from the published research literature on professional licensing and assessment, the federal statutory and regulatory record applicable to appraiser oversight in the United States, and the publicly available regulatory frameworks of comparable U.S. licensed professions. The brief is informational and is not a statement of policy of the Appraiser Qualifications Board (AQB), The Appraisal Foundation® (Foundation), or any state appraiser regulatory agency. It does not commit any party to any particular position or course of action. The Real Property Appraiser Qualification Criteria (Criteria) are revised through the public exposure-draft-and-comment process, which is conducted separately from this brief.