The nature and scope of “informal settlers” are defined according to specific historical conditions, social conflicts, and spatial configurations. In contrast with the prevailing negative features of slums, other types of informal dwelling are here distinguished and a more nuanced account of informal living given. This approach has consequences for the study of land tenure in terms of its diversity, security, and possible formalization. It is argued that investigations on informality need to focus on the power struggles over resources and the meanings and perceptions of informality, in addition to the systemic constraints for informal settlers, instead of only identifying social practices not in accordance with dominant conventional and legal norms.