Convention jurisprudence concerning the private sphere is an especially dynamic field of human rights law. In this short chapter we clarify the meaning of the term 'private sphere', make some general observations on the salience of relevant case law, and then introduce the four substantive chapters. For the purposes of this Part, the term 'private sphere' refers, firstly, to the most intimate aspects of human experience. Addressed directly under Article 8, protection of one's private and family life, is critical for human flourishing. As the chapters in this section demonstrate, the Strasbourg Court has moved beyond traditional human rights doctrine, which tended to consider the inner circles of our lives as a zone to be safeguarded from an overreaching state. Secondly, the term 'private sphere' denotes the application of Convention provisions to the activities of non-state actors. Here too the ECtHR has developed the frontiers of human rights standards in both what Donnelly describes as the partially private sphere (where private actors perform governmental functions or provide public services pursuant to governmental outsourcing or privatisation) and the 'wholly private sphere' (which refers to relationships between private actors).