A U.S. consensus committee has recommended the return of rock and soil samples as the next logical step for Mars exploration and the highest priority in solar system science. Sample return also answers NASA's call for new missions to be "aspirational" (read: bigger and better by an order of magnitude and going where no one has gone before). But with budget cuts, even Mars sample return is no shoo-in. Next month a NASA committee will report on how the agency might proceed with Mars exploration. Ominously, all the options will involve hitching planetary science to human spaceflight—a chancy proposition. The outcome could determine whether Mars, or any planetary body, will rate one of NASA's multibillion-dollar "flagship" missions in the next decade.