Apart from their fundamental scientific interest, environmental issues such as climate change, biodiversity loss and pollutions of air and water are a major concern for the society at large, including citizens, policy makers and economic stakeholders. Within the Paris-Saclay University (UPSaclay), research laboratories have competences covering the major disciplinary fields necessary to tackle environmental issues, e.g. biology, physics, chemistry, geosciences, agronomy, ecology, economy, human and social sciences. They have developed methodologies based on recognized observational, modelling and analytical tools, benefitting from two labex (L-IPSL and BASC) and the GIS “Climat Environnement Société”. Since 2012, the transversal working group on environment of Paris-Saclay (GT environnement), which recently evolved into the Institut des changements socioenvironnementaux (ICSEN) aims to strengthen this strong research potential through the development of a structured dialogue between involved scientists but also with stakeholders and economic actors looking for a scientific and technological expertise on environmental issues. This general objective will be achieved by initiating new interdisciplinary projects built on innovative and formalized social and economic participatory assessment procedures, complementary to projects funded by the already existing labex. In parallel this institute will coordinate UPSaclay’s training programmes related to relevant environment and sustainability issues.

The next decades will probably experience major environmental changes from local to planetary scale. New approaches are necessary to characterize these changes, their temporal evolution and impact on natural and human environments at the different scales, together with the many feedbacks applying. These approaches have to integrate methodologies across disciplines such as physical and life sciences, geoscience, social and human sciences. Such a requirement is now clearly recognized by international programmes like “Future Earth”, which aims at supporting research projects based on interdisciplinary approaches on various themes, e.g. Global Sustainable Development and Transformations towards Sustainability (http://www.futureearth.org). At national level, the French government is starting the preparation of the second version of the national adaptation plan to climate change, which will require specific but also transversal actions.

Yet today it is increasingly obvious that interdisciplinary science, while being a necessary condition in order to face global environmental change, is not sufficient. There is a call for transdisciplinary practices (Blanchard and Vanderlinden 2013, Mauser et al. 2013, Klenk and Meehan, 2015) focused on the need for deeper transformation (O’Brien, 2012), and the associated need for a better integration of science, society and decision making, with actions associating all stakeholders.