Macramolecular crystallography with a third-generation synchrotron source

The European Synchrotron Radiation Facility (ESRF) at Grenoble, France, is a 6 GeV machine producing hard X-radiation that can be used for pure and ap plied research in a wide range of disciplines including physics, chemistry, structural biology, materials science, the earth sciences, engineering and medicine. The overall nature of the machine will be described, including t he features that give rise to the notation 'third-generation source'. The E SRF is equipped with a number of beamlines which can be used for macromolec ular crystallography. Applications include the use of very small crystals, large unit cells, data collection at high resolution, anomalous dispersion measurements for phase determination and time-resolved studies. Key feature s of these applications will be described.