After successful testing at the Raytheon facility in Danbury, Connecticut, the completed SAAO adaptive optical system has been shipped to the AEOS site on Haleakala, Maui, Hawaii. The system is undergoing final integration with the AEOS observatory. This paper describes the adaptive optics system design, including an overview of al major subsystems, the electronics, and the software. We discuss the design trades and system engineering that led to the final configuration. Also included is a review of opto-mechanical aspects of the system.