An international workshop on metrology for X-ray and neutron optics, the first of its kind, was held March 16-17, 2000, at the Advanced Photon Source at Argonne National Laboratory. Engineers and scientists from around the world met to evaluate current metrology instrumentation and methods used to characterize the surface figure and finish of long, grazing-incidence optics used in synchrotron radiation beamlines, and to consider future needs for synchrotron, FEL, and neutron sources.