Probably there is no single research innovation in laboratory and experimental geophysics with more potential than proposed applications of synchrotron radiation. Three large specialized machines for these and other applications are to come on line this year, including the existing synchrotron rings at Stanford University (SLAC, Stanford Linear Accelerator Facility), Cornell Univesity (CHESS, Cornell High-Energy Synchrotron Source), and a totally new facility at Brookhaven National Laboratory (NSLS, National Synchrotron Light Source). These synchrotrons are special in that they release almost pure white X radiation of exceedingly high intensity that can be utilized in a variety of diffraction experiments. This will be the first time sufficient X ray intensity has been available to track the atom-by-atom kinetics of rapid phase transitions at one atmosphere and at high pressures in special apparatus. It is also the first time that experiments at high pressures and temperatures about 1000°C and extending to 4000°C, thus duplicating conditions as intense as those at the earth's core-mantle boundary, can be analyzed by in situ X ray diffraction.