Interview with Charlotte Halpern -1st l ines :A New Research Area Interest in the results of public policies is growing among public institutions and civil society, while the environmental crisis is gaining importance on every level. Sciences Po has therefore expanded the scope of its Laboratory for interdisciplinary evaluation of public policies (LIEPP), in collaboration with Université de Paris, to include environmental issues. Presentation by Charlotte Halpern, head of this new programme. You recently took charge of LIEPP’s new research area, ‘environmental policies’. Why is it important to evaluate environmental policies? Charlotte Halpern: Environmental transformations and the climate emergency justify the introduction of a series of reforms and measures to accelerate the transition of modern societies and economies towards carbon neutrality by 2050. These measures also aim to reduce social/environmental inequalities and to ensure sustainable transformation of territorial development strategies. This new generation of public policies adds another layer to the decades of promises concerning environmental protection, sustainable development, green growth and energy transition. The climate agenda is attracting unprecedented attention as well as strong opposition from European citizens, who express their opinions in the streets, via social media and the ballot boxes. This research area analyses the efforts made by public policies in the field of the environment, in the widest possible sense, including sustainable development, climate change, green growth and its more recent additions, energy and ecological transitions, to explain the transition dynamics at play and to enlighten the decisions of stakeholders and decision makers. What role is played by public policies and stakeholders in driving and coordinating these transitions? What resources are implemented to put these transversal objectives into operation? How, using which levers, at what pace and to what extent will these schemes transform our current systems? What sectoral and territorial variations can be seen? What results have been observed? Which social groups, territories and economic sectors benefit most? What effects do they have on political systems and their varying capacities to integrate climate issues?