At least 14 space agencies have identified ‘in situ resource utilization’ as a necessary capability for long-duration missions, including crewed missions to the Moon, Mars and deep space. Attention is focused on the potential production of rocket fuel from ice and water-bearing minerals. If fuel can be sourced in space, it will not need to be lifted, at great expense, from Earth’s surface. But while the mining of asteroids and other celestial bodies offers benefits, it will also create risks. Mining that is motivated purely by resource extraction could overlook or even destroy important scientific information, while physical interactions with an asteroid could alter its trajectory and, in some circumstances, potentially create a human-caused Earth impact risk. There are presently two competing efforts to develop widely agreed rules on space mining. The first is an industry-friendly effort in which the United States is engaging in bilateral negotiations with dozens of states, encouraging them to sign the non-binding Artemis Accords. The second is a multilateral effort that fully considers the interests of non-spacefaring states and is taking place in the United Nations Committee on the Peaceful Uses of Outer Space.