The main objectives of this manual are (1) to provide a comprehensive description of the methodology employed by the OECD to calculate indicators of agricultural support, by using descriptive text, mathematical equations and empirical examples, (2) to describe the economic theory and principles which underlie this methodology, (3) to illustrate the practical application of this methodology, including how best to deal with data limitations, and to assist those wishing to replicate the method and apply it to other countries or commodities, and (4) to explain how the indicators can be used for