The Paul Scherrer Institute (PSI) is the largest research centre for natural and engineering sciences in Switzerland, conducting cutting-edge research in three main fields: matter and materials, energy and environment, and human health. PSI develops, builds and operates complex large-scale research facilities. Primarily financed by the Swiss Confederation, PSI is part of the Domain of the Swiss Federal Institutes of Technology , along with the Swiss Federal Institutes of Technology, ETH Zurich and EPFL Lausanne, as well as Eawag (Swiss Federal Institute of Aquatic Science and Technology), Empa (Swiss Federal Laboratories for Materials Science & Technology) and WSL (Swiss Federal Institute for Forest, Snow and Landscape Research).