Greenhouse gas emissions decreased by 15% between 1990 and 2017 (Kyoto scope, excluding LULUCF). At the same time, the population increased by 15% and the GDP by 52% over the same period. Today, among the developed countries, the territorial emissions per inhabitant of the French are among the lowest in the world. This testifies to the effort to decarbonise the economy already made in France, and which will be further amplified by 2030 and 2050. But it also testifies to the tertiarization of the French economy, which is correlated to a drop in its industrial activity. Moreover, most of the budgetary expenditure for the fight against climate change is oriented towards the long term. Indeed, they concern research and transport infrastructure in the modes that emit the least greenhouse gases. This is also the case for tax expenditures, most of which aim to support the renovation of housing. Finally, this is also the case for regulatory action, which obliges investments to make significant energy savings over their entire life cycle. In the longer term, research and development funding is likely to have the greatest impact. Thus, support for the emergence of green sectors and the development of renewable energies (support for onshore and offshore wind power, photovoltaics, renewable gas, biomass) is an essential lever for meeting the challenge of transition energy, which alone will allow a response commensurate with the challenge of climate change, in terms of controlling energy consumption and more generally of lifestyle and low-emission and economical production methods. As detailed above, France has set itself a long-term objective, carbon neutrality on the horizon Effects on emission reduction