The “Stiftung Deutsches Elektronen-Synchrotron”, DESY, is one of the world's leading accelerator centres for the investigation of the structure of matter with approximately 2,300 employees and the most advanced scientific, technical and administrative infrastructures. DESY develops, operates, and uses complex accelerators, detectors and observatories for photon science, particle and astroparticle physics. The laboratory hosts and is a member of several large, international collaborations contributing to the advancement of science exploiting large-scale analytic research infrastructures. On campus, DESY operates PETRA III, the most brilliant synchrotron radiation source worldwide, and the soft X-ray free electron laser (FEL) FLASH which was the first X-ray FEL worldwide. PETRA III and FLASH are user facilities with roughly 2,500 unique users per year from all over the world. In addition, DESY is responsible for constructing and operating the 1.7-kilometre long superconducting linear accelerator of the European X-ray Free Electron Laser (European XFEL).