The Uniform Standards of Professional Appraisal Practice (USPAP) are the generally recognized ethical and performance standards for the appraisal profession in the United States. USPAP was adopted by Congress in 1989, and contains standards for all types of appraisal services, including real estate, personal property, business and mass appraisal. Compliance is required for state-licensed and state-certified appraisers involved in federally-related real estate transactions. USPAP is updated every two years so that appraisers have the information they need to deliver unbiased and thoughtful opinions of value. You can find Q&As here.
Additionally, the Foundation, in partnership with the US Department of Justice, is publisher of the Uniform Appraisal Standards for Federal Land Acquisitions, commonly known as the "Yellow Book." To purchase an interactive electronic PDF copy of the Yellow Book, click here (paper copies for purchase will be available soon).
Appraisal Standards - USPAP
Appraisal Standards - Yellow Book