The Center for Environmental Systems Research (CESR) was founded 1994 as an interdisciplinary research unit of the University of Kassel (UNI KASSEL). The Center focuses on environmental problems in the context of climate change and resource consumption. Systems orientation and the use of systems analysis tools characterize the Center’s approach to research questions. Scientists with backgrounds in various natural and social sciences are working together, including those with expertise in hydrology, civil engineering, geo-ecology, informatics as well as psychology, philosophy, and political sciences. Research topics are climate impact research, sustainable land- and water management, life cycle analyses, and changes in consumer behavior. Close relationships exist, especially through the four professorships at the Center with numerous research domains of the University as well as other German research institutions, such as the Wuppertal Institute for Climate, Environment and Energy.