This guideline presents a spreadsheet template under Excel initially developed by Tom Randolph at the West African Rice Development Association in collaboration with the former Food Research Institute at Stanford. This template has been extensively used to compute the comparative advantages of the rice subsector in West Africa countries in the late nineties and early year of the 2000 decade. It has also been used in the framework of the Comparative Advantages Study (CAS) of selected Syrian agro-food commodity chains implemented by the staff of the National Agricultural Policy Centre of the Syrian Ministry of Agriculture and Agrarian reform with the support of the FAO. This document presents how to use the template to compute Policy Analysis Matrix. The document is organized around 4 sections: - Section 1 introduces the structure of the spreadsheet and presents its different parts in details, - Section 2 explains how the PAM is computed from the data keyed in, - Section 3 provides information on how to handle the spreadsheet, - Section 4 provides examples of possible adjustments and additional functionalities to the basic PAM template.