In this chapter, we examine how agent technology might be utilized in flight software (FSW) to enable increased levels of autonomy in spacecraft missions. Again, as stated in the Preface, our discussion relates exclusively to uncrewed assets (robotic spacecraft, instrument platforms on planetary bodies, robotic rovers, etc.) or assets that must be capable of untended operations (e.g., ground stations during “lights-out” operations). The basic operational functionality discussed in Chap. 2 is accounted for and allocated between flight and ground, and between agent and nonagent FSW. Those technologies required to enable the FSW design are touched upon briefly, and new autonomous capabilities supportable by these technologies are described. Next, the advantages of the design from a cost-reduction standpoint are examined, as are the mission types that might benefit from this design approach.