This guidebook supports countries who intend to undertake self- or peer review of fossil fuel subsidies by clearly explaining the different elements of a review and providing case studies as to how countries have approached and undertaken reviews. The guidebook takes readers through a step-by-step approach to identifying and defining fossil fuel subsidies, reviewing the scope of a review, measuring subsidies, evaluating them and identifying the next steps towards the reform of subsidies. Country case studies are included from China, Finland, New Zealand, Peru and Sweden. Practical annexes are included that explain international commitments on fossil fuel subsidies, templates for identifying and reporting fossil fuel subsidies, and principles to follow for a review process. The guidebook supports country efforts around transparency on fossil fuel subsidies as the first step towards reform by sharing lessons and experiences from other countries. The guidebook is available for download on the IISD website.