It was decided early in the New Millennium Program's conception of missions that a complete testing and proving out of the technologies would require flying them on missions that bore strong resemblance to science missions of the future.

Another constraint on the missions derives from the need to return results promptly to future users about whether or not the technologies work in space. With Deep Space 1, it was decided that the primary mission should last no longer than about one year. This allows sufficient time to conduct an exciting mission and to exercise the technologies under a wide range of conditions without forcing eager potential users to wait unreasonably long before being confident about their use.