Historically, segmented optics similar to those used in BBXRT and ASTRO have achieved resolutions of a few arc minutes. Achieving substantially better performance requires significant improvement in both the optics themselves and how the optics are assembled and mounted to flight structure. While techniques for improving the optics themselves are underway at Goddard Space Flight Center (GSFC), Columbia University, and Smithsonian Astrophysical Observatory (SAO), here we address how the optics are assembled and mounted to flight structure. We have developed a concept for mounting large numbers of nested, segmented optics which require sub micron accuracy. This methodology uses lithographically defined and etched silicon alignment microstructure. A precision assembly station, incorporating the silicon micro structures is used to position the optics which are then bonded to a flight structure. The advantages of this procedure are that the flight structure has relaxed tolerance requirements and the precision assembly tooling can be reused. We show the positional requirements of the precision tooling as well as the mechanical requirements of the tooling itself.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.