All public policy tools designed to promote ecological transition have distributional effects, i.e. they do not affect social groups in the same way, particularly the rich and the poor. This article examines the causes of these distributive effects. The most relevant distinction is not between economic and regulatory tools, but between those that target newly marketed goods and services and those that target all existing goods and services; the latter have a much more marked distributive effect. Neutralizing these effects requires detailed studies that take into account not only household income, but also a whole range of socio-economic characteristics.