This report presents the results of an Ex-Ante Carbon-balance Tool (EX-ACT) Greenhouse Gas appraisal of the project “Sustainable management of critical wetland ecosystems” in Gabon. The project aims to improve protection of biodiversity in selected forested wetlands on the Ramsar list (Bas Ogooue, Monts Birougou and Petit Loango/Sette Cama). This will be achieved through knowledge creation and the development of conservation measures for the management of sustainable wetlands. The project seeks to cover 30 000 ha of forest area under sustainable forest management, benefiting 70 000 households. The GHG appraisal shows that the project has strong potential for climate change mitigation: -444 658 tCO2-e per year, if the project is implemented successfully.