Intimacy is a modern category and the frontier between the public and the private is a partition which has its historical origins in the States recognising the rule law and the democracies taking shape in the 18th and 19th centuries. This article, an introduction to the dossier, argues that the frontiers between the intimate and the political are being redefined, while intermediary spaces between the public and the private are being created which some authors refer to as “social intimacy” or “commons.” The article examines in turn three ways of approaching the question in the social sciences. We begin with the history of the evolution between the public and the private sphere. Secondly, we consider the sociology of the debates concerning the possibilities of the Internet and the digital world which give rise to new terms like the “right to oblivion,” anonymity, the “protection of personal data,” or again “privacy.” Finally, we turn to the sociology of movements for the globalisation of habits or morals and forms of collective action for equality.