Gauss is a consultancy firm based in Madrid (Spain), which delivers an extensive experience across all areas of climate change, air quality, energy and environment. Gauss is specialized in applied research - data analysis, IT, elaboration of customized tools, application of good practice guidance for international reporting and sustainable development policies evaluation. The team is composed by engineers and researchers with a multidisciplinary background - statistics, economics, environmental sciences and programming - as well as multilingual competences and broad international experience. Gauss is composed by internationally recognized UNFCCC lead reviewers of national inventories, national communications/biennial reports and biennial update reports, with a sound experience in national inventories compilation, quality control & quality assurance, implementation of improvement plans, mitigation and adaptation policies and measures, risks management, identification of technology, financial and capacity building needs and MRV (monitoring, reporting and verification) systems. Gauss is also specialized in the development of inventories, projections and policy analysis of air quality pollutants, integrating the team several CLRTAP reviewers of national inventories. This experience provides a complete knowledge of the synergies between climate change and air quality, including their information systems and reporting requirements. Energy balances, energy modelling, design & assessment of low-carbon strategies and scenarios, infrastructure studies, and assessment of energy policies as well as the areas of industrial pollution, circular economy, green-growth and environmental accounts and statistics are among the competences of the team too. Like the Gaussian bell curve, our goal is to develop tools to express and decode complexity in a simple and understandable way for everyone.