Fugitive emissions from fuels are an important source of greenhouse gases (primarily methane (CH4) and to a lesser extent carbon dioxide (CO2) and nitrous oxide (N2O)) for a number of Parties included in Annex I to the Convention. The Revised 1996 IPCC Guidelines for National Greenhouse Gas Inventories (1996 IPCC Guidelines), as elaborated by the IPCC Good Practice Guidance and Uncertainty Management in National Greenhouse Gas Inventories (IPCC good practice guidance), contain methodologies that are being used by many Parties to estimate fugitive emissions from fuels. These methodologies range from tier 1 methods using default emission factors to rigorous country-specific methods using country-specific emission factors. Although the 1996 IPCC Guidelines and the IPCC good practice guidance have proved to be useful tools for the estimation of fugitive emissions from fuels, some areas for further improvement have been identified. This document contains suggestions that could be considered by the IPCC in its work on the development of the 2006 IPCC Guidelines for National Greenhouse Gas Inventories and by Parties in the preparation of national greenhouse gas inventories.