The X-Ray Telescope High Resolution Mirror Assembly (HRMA) designed by American Science and Engineering (AS&E) and Smithsonian Institution Astrophysical Observatory (SAO) was developed, manufactured, assembled, and tested by Perkin-Elmer under contract to AS&E. This paper describes each phase of its fabrication and testing except for the surface roughness measurement and the optical coating which are discussed in separate papers. Particular emphasis is placed on the achievement of the circumferential variation in slope, A (A R), and its measurement during the loose-abrasive grinding operations. Also discussed, at length, are the optical figuring, surface smoothing via submerged polishing, and figure measurement using a semi-automated fringe scanner and modular interferogram analysis computer programs. The optical testing used during the assembly operation is reviewed and the test equipment and test methods are described. The pertinent specifications of the High Resolution Mirror Assembly and achievements of the program are summarized.