With the four candidate strategies completed to the preliminary stage, selection of one for further development was accomplished by measuring how well each strategy met the mission objectives. Some of the objectives were easy to assess due to their simplicity and straightforwardness, yet some proved challenging to assess due to their highly subjective nature. Black and white objectives such as "international cooperation" could be easily met by all strategies; therefore, these types of objectives were not instrumental in narrowing down the strategies in the evaluation process. However, highly subjective requirements such as "increased public interest and support" provided some separation between the strategies.

The "subjective" objectives that highlighted differences in the strategies were 1) human expansion beyond Low Earth Orbit, 2) technology advancement, 3) public space awareness and support, and 4) financial burden (cost). To help in down-selecting a strategy, all strategies were compared in these areas and a list of strengths and weaknesses was developed. After evaluating the strengths and weaknesses of each strategy, it was decided that the "Step-by- step" strategy had the most potential. It was determined that it provided the best long term exploration plan (human expansion beyond Low Earth Orbit) and allowed for the most flexibility to meet existing and unforeseen objectives and requirements.

In assessing the "Step-by-step" strategy in terms of financial burden to the participating countries, it was felt that the strategy would be the best for distributing the costs over a longer period. Past space programs have demonstrated that investors and politicians find large expenditures more palatable when spread over a longer period of time. A program with large up-front monetary expenditures, such as a Mars mission, stands a lower chance of approval unless another source of motivation exists (e.g. the Apollo Moon race).

The potential disadvantage of a lengthy "Step-by-step" strategy is that over the long run the actual cost could be more than that of a fast paced exploration strategy. The ballooning cost of the International Space Station provides a good example of how programs can become more costly the longer the implementation. Another weakness that arises as a result of a long project duration is that it will not drive technology development. Since the "Step-by-step" strategy occurs over a long period, instead of driving technology development it would make use of the technology of the day in its design to reduce cost and risk. The other candidate strategies were heavily dependent on very specific technology development to succeed. This reliance injects schedule and cost uncertainty into program development. The "Step-by-step" strategy is more immune to this hazard.

Space awareness for this strategy also has positive and negative components. On the positive side, since a main thrust of this strategy encourages space tourism, space awareness must increase; however, on the negative side, a lengthy strategy might result in a loss of public support over time. Regarding exploration, the many destinations and possibility of immediate implementation were attractive. Considering all these "subjective" objectives, the "Step-by-step" strategy had the best pro-to-con ratio; consequently this strategy was fully developed beyond the preliminary stage.

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