FAO supports its Member Countries with data, guidelines and technical expertise towards an enhanced global knowledge base on GHG emissions and mitigation potentials. The Monitoring and Assessment of GHG Emissions and Mitigation Potentials in Agriculture – MAGHG Project of the Climate, Energy and Land Tenure Division’s Mitigation Programme (MICCA), in close collaboration with the FAO Statistics Division and the FAO Forestry Division UN REDD Programme, has developed and made available relevant activity data, GHG emission estimates databases and analysis tools through the FAOSTAT database. These products are used in regional and country-level capacity development activities that support practitioners in assessing and reporting GHG emissions from agriculture and land use categories, with a view to strengthening their national processes, with a focus on preparation and submission of GHG Inventories, Biennial Update Reports (BURs) and NAMAs. This Manual provides Member Countries with a tool and methodology to help identify, build and access the minimum set of activity data needed for GHG estimation. Required data is largely drawn from country’s official national agricultural and forestry statistics, as disseminated in FAO’s corporate database FAOSTAT, and integrated by geo-spatial data obtained from recognized international sources. Users are provided with step-by-step guidance on how to use this minimum set to build a default, yet complete national GHG emission dataset for agriculture and land use, which follows the default, Tier 1 approach of the Intergovernmental Panel on Climate Change (IPCC) Guidelines on National GHG Inventories.