With the help of outside inputs, NASA is defining possible strategies to be used to work toward the goals of the SEI. Some paths make extensive use of ISMU to build up our presence in the solar system quickly. Others take a more restrained approach, relying almost completely on bringing material from Earth as part of an overall attempt to lower the cost of the program by trading off scientific and operational capabilities. As the program develops over the next several years, the interplay of capabilities and investments will be more completely understood for the program as a whole. A near-term focus of the SEI is on technology development, with a search for innovative ideas that have a high leverage impact on cost, schedule, and performance. Since the ISMU program affects all these measures of performance, it is sure to play a major role in this effort.