This chapter examines Michel Foucault’s concept of technologies of the self within his broader genealogy of Western subjectivity. It reconstructs the three historical configurations through which these practices emerged: the Socratic–Platonic emphasis on the care of the self, the Greco-Roman “arts of existence,” and the Christian transformation that bound self-formation to obedience confession, and truth-telling. The chapter also analyzes Foucault’s self-critique after the first volume of The History of Sexuality, showing how the notion of technologies of the self enabled him to move beyond a purely strategic model of power toward a framework centered on subjectivation and practices of freedom. Finally, it reviews contemporary debates—including critiques by Hadot, Habermas, and Žižek—and considers recent extensions of the concept in relation to digital self-tracking and algorithmic governmentality.