This CSIS Report examines the strategic implications of manned space exploration. The current phase of exploration is coming to an end, and nations are seeking the next step. The decisions of the United States and its partners on the future of space exploration will determine the strategic situation in space. There are difficult issues to consider in moving ahead: the target of exploration beyond LEO, the balance between manned and unmanned programs, the future of partnership and cooperation in space, and the ultimate fate of the ISS. How Western space powers answer these questions will determine both the pace and the future direction of exploration in space.