The Space Telescope (ST) Pointing Control System (PCS) slews the optical axis from one target star region of the celestial sphere to the next, and maintains precision pointing at the target star. The spacecraft digital computer processes the attitude and rate sensor data to generate torque commands for the reaction wheels. The PCS has four major elements: the command generator, the control system, the attitude reference processing, and momentum management. The ST Pointing Control System (PCS) is designed to meet the fine pointing performance of 0.007 arc-sec stability, maneuver the telescope, and provide the capability for deployment from, and retrieval by, the Space Shuttle. The PCS objectives are met using fine guidance sensors (FGS) for attitude and derived rate information to achieve fine pointing, and rate gyro assemblies (RGA) for rate and attitude information during maneuvers. The emphasis in this paper is on acquisition methodology for pointing control, flexibility effects of the large optics, and simulators for development testing.