Automation must be carefully validated before it can lead to a more operable autonomous system. The careful integration of automated functions is considered to be fundamental to the achievement of operational autonomy. Without significant testing, automation may reduce performance and/or operability, actually leading to less autonomy and even more significant human attention requirements. In addition to traditional software engineering methods, a development environment for simulations and mixed hardware/software testbedding with the ability to support injection of simulated faults, is fundamental to the successful application of automation. The use of a testbed to build a virtual spacecraft in order to be used as an automation testbed with the ability to migrate automation proven in the testbed will help ensure that automation does in fact lead to increased operability. For example, a fault detection and reaction automation can be prototyped, tuned, and tested in the testbed, then migrated to the ground operations computers for further testing and operator concu,'rence, followed by migration onboard once the automation is "trusted."