Space-based Geoengineering (GE), understood as the deliberate and benevolent manipulation of planetary environment from or in space may be regarded as a possible option if current mitigation or adaptation measures to Climate Change prove insufficient. It could be categorized into two types, both intended to achieve similar objectives: (a) GE technologies directly aimed at altering the environment’s composition, and (b) GE solutions based on the use of novel untested technologies, like space-based solar shields. Should such a path be pursued, their use would require careful legal regulation to ensure compliance with the Outer Space Treaty (1967), especially Art. IX aimed at ensuring protection of the natural environment lato sensu. Nevertheless, to address potential challenges arising from unfamiliarity with this new type of activity, legal experts and decision-makers may need to review legislations and even consider whether new approaches should be applied, rather than a strict, literal reading of the existing International Space Law (ISL).