Stephane La Branche is an independent transition sociologist and scientific coordinator of the IPBC/GiecO. His research (more than 50 completed or in progress) focuses on the drivers of change and non change, relative to practices, perceptions and social representations relative to climate, energy, air quality and biodiversity, in order to find appropriate and effective responses. As a guest expert in the process of the Law on Energy Transition in France and in the development of the three national strategy for adaptation to climate change, He has also contributed to the setting up of several Territorial climate strategies. His research has led him to be an expert reviewer for two IPCC reports. The results of his research have been integrated into transition policies and strategies (mobility, energy, urban planning, information and support campaigns, etc.) for private operators, companies, public and associations and into prospective scenarios for 2050.