The Precision Segmented Reflectors (PSR) project is described in this paper. The project, which involves the close cooperation of two NASA Centers, represents a first step toward developing the technology base needed to support future advanced astrophysics missions. The focus of this project is to develop a lightweight, low cost option for building large reflecting telescopes that can be assembled in space. Four major technology areas, i.e., reflector panels, structures, controls, and system integration are being developed. A principal driver for PSR technology development is the proposed Large Deployable Reflector (LDR) telescope. The technologies being developed under the PSR program are, however, generic and can be applied to many future missions such as optical communications, optical interferometers , and other missions requiring large reflectors.