The planned creation of colonies on said celestial bodies implies the establishment of permanent human communities on them as well as the creation of permanent structures on (or below) their surface. Obviously, this will be a new phase in the context of space use and exploration. Although, in the light of international law and space law, there can be no colonies (in the traditional sense) in outer space, plans for inhabiting the Moon or Mars can be legally justified in the context of the freedom of exploration and use of outer space. However, the spirit and the provisions of the space treaties in force do not seem able to provide a robust legal framework for the creation of such “space communities”. Consequently, the adoption of a specific, ad hoc legal framework could substantially facilitate the functioning of permanent space settlements. Νo one, however, can rule out the prospect of these newly founded communities opting for an independent and autonomous course through the adoption of their own laws.