The EMEP/EEA air pollutant emission inventory guidebook 2009 provides technical guidance for preparing national emission inventories. It is a revised and updated version of the EMEP/Corinair guidebook, developed under the Corinair initiative. The guidebook contains the most recognized emission estimation methods used in air pollution studies in Europe and the UNECE geographical area. It has evolved over a long period and is now an essential tool for compiling comparable and consistent air pollutant emissions data in Europe. Access to high-quality air pollutant emissions data is crucial for supporting sound policy-making. It helps shape environmental priorities, improve air quality modelling, assess compliance with national and international targets, and evaluate the effectiveness of policy interventions in protecting human health and the environment. Air pollutants and greenhouse gases are often emitted from the same sources, so well-designed mitigation strategies can deliver significant co-benefits in terms of improved air quality and reduced greenhouse gas emissions. The revised guidebook is compatible with and complementary to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories. The guidebook is intended as a general reference and, in conjunction with the UNECE Reporting Guidelines, for use by parties reporting emissions to the LRTAP Convention and its protocols, and for use by European Union Member States for reporting under the National Emission Ceilings Directive. It is also the recommended source of methodology information for preparing emission inventories of ozone precursors and sulphur dioxide following the 2006 IPCC Guidelines. The guidebook complements the IPCC Guidelines and is frequently used as a reference document by researchers. The guidebook is structured according to the Nomenclature for Reporting (NFR) as defined in the Reporting Guidelines to the LRTAP Convention. The NFR reporting nomenclature is consistent with the one used for reporting under the UNFCCC, expanded for particular sources of air pollution. The guidebook has been closely harmonised with the IPCC Guidelines by introducing the 'Tiers' approach and providing decision trees to support the selection of appropriate methodologies. This contributes to the harmonisation of international and EU greenhouse gas and air pollutant emissions reporting. The guidebook is available in electronic form via the EEA's website: www.eea.europa.eu/emep-eea-guidebook. It provides procedures to enable users to compile emission inventories that meet quality criteria for Transparency, Consistency, Completeness, Comparability, and Accuracy (TCCC criteria). It provides estimation methods and emission factors for inventory compilers at various levels of sophistication. The guidebook may be used for general reference or, in conjunction with the LRTAP Reporting Guidelines, by parties to the Convention to assist them in meeting their emission reporting obligations under the Convention and its protocols. It must also be used by the Member States of the European Union to fulfill their emissions reporting requirements under the NEC Directive. The guidebook may be used to prepare emission inventories of substancesThe EMEP/EEA air pollutant emission inventory guidebook 2009 provides technical guidance for preparing national emission inventories. It is a revised and updated version of the EMEP/Corinair guidebook, developed under the Corinair initiative. The guidebook contains the most recognized emission estimation methods used in air pollution studies in Europe and the UNECE geographical area. It has evolved over a long period and is now an essential tool for compiling comparable and consistent air pollutant emissions data in Europe. Access to high-quality air pollutant emissions data is crucial for supporting sound policy-making. It helps shape environmental priorities, improve air quality modelling, assess compliance with national and international targets, and evaluate the effectiveness of policy interventions in protecting human health and the environment. Air pollutants and greenhouse gases are often emitted from the same sources, so well-designed mitigation strategies can deliver significant co-benefits in terms of improved air quality and reduced greenhouse gas emissions. The revised guidebook is compatible with and complementary to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories. The guidebook is intended as a general reference and, in conjunction with the UNECE Reporting Guidelines, for use by parties reporting emissions to the LRTAP Convention and its protocols, and for use by European Union Member States for reporting under the National Emission Ceilings Directive. It is also the recommended source of methodology information for preparing emission inventories of ozone precursors and sulphur dioxide following the 2006 IPCC Guidelines. The guidebook complements the IPCC Guidelines and is frequently used as a reference document by researchers. The guidebook is structured according to the Nomenclature for Reporting (NFR) as defined in the Reporting Guidelines to the LRTAP Convention. The NFR reporting nomenclature is consistent with the one used for reporting under the UNFCCC, expanded for particular sources of air pollution. The guidebook has been closely harmonised with the IPCC Guidelines by introducing the 'Tiers' approach and providing decision trees to support the selection of appropriate methodologies. This contributes to the harmonisation of international and EU greenhouse gas and air pollutant emissions reporting. The guidebook is available in electronic form via the EEA's website: www.eea.europa.eu/emep-eea-guidebook. It provides procedures to enable users to compile emission inventories that meet quality criteria for Transparency, Consistency, Completeness, Comparability, and Accuracy (TCCC criteria). It provides estimation methods and emission factors for inventory compilers at various levels of sophistication. The guidebook may be used for general reference or, in conjunction with the LRTAP Reporting Guidelines, by parties to the Convention to assist them in meeting their emission reporting obligations under the Convention and its protocols. It must also be used by the Member States of the European Union to fulfill their emissions reporting requirements under the NEC Directive. The guidebook may be used to prepare emission inventories of substances