To make the best use of Mars’ moons, we need to transpose the principle of rocket staging to the environment of the Martian system. The rocket that launches from the surface of Mars has no need to go all the way to Deimos: upon arrival at Phobos, at the exit of Mars’s energy pit, it can pass on its payload to a lightweight shuttle designed solely for the upper leg. The first stage remains within the lower area, the second stage within the higher one. The “plus” offered by Phobos is that neither stage needs to transport the other, and both are reusable.