short communications
A workshop entitled Potential Future Applications in Structural Biology of an X-ray Free-Electron Laser at DESY was held at Hamburg, Germany, on 4-8 July 1999. The aim of the workshop was to identify and discuss potential applications in structural biology using the specific beam properties of the planned X-ray free-electron laser at DESY, Hamburg. The workshop focused on proposals in X-ray crystallography, spectroscopy, microscopy and holography. In the discussions during the workshop, the response of biological material to the expected high photon flux and its time dependence played a central role. Technological aspects in data recording and image interpretation were covered as well. There was general agreement that an X-ray free-electron laser source with its specific source parameters could offer unique opportunities for novel experiments in structural biology, complementing current synchrotron facilities. The realization of future applications will be challenged by the handling of large high-energy doses on the biological specimen and the development of equipment capable to respond to a pulse time structure in the femtosecond range.