10th Call for Proposals for User Experiments: Regular Proposals (including Cross-Instrument Use) and Sample and Protein Crystal Screening Proposals. The 10th call for regular proposals at the European X-Ray Free-Electron Laser Facility (European XFEL) is open until Friday, 09 December 2022, at 16:00 (local Hamburg/Schenefeld time / Central European Time – CET) for the seven scientific instruments planned to be in operation the second semester of 2023.