‘titrebSummary’/titrebThe more often, debates on how to achieve more sustainable mobility focus on people’s travel habits, but the transport system is also strongly influenced by the behaviour of the institutions. The article discusses the changes introduced by the US federal authorities in transport planning and financing mechanisms through two laws, namely the Intermodal Surface Transportation Efficiency Act adopted in 1991 and the Transportation Equity Act for the 21st Century adopted in 1997. Despite their limitations, these pieces of legislation, supported by strong coalitions of lobbyists, have had a strong impact on US transport policy. They are rich in lessons for other countries, both in the political process and in the interactions between the different levels of decision making. A top-down approach at federal level can be useful to foster a bottom-up planning process at local and regional level. The successful introduction of reforms in an unbalanced and sustainable transport system, characterised by a high number of passenger cars, excessive development of automotive infrastructure and intensive use of cars, shows that there is real scope for change.