Michel Foucault, who was born in 1926 into an upper-middle-class family, came of age in post-World War II Paris, studied with Louis Althusser, and rose to intellectual prominence in the 1970s, died on June 25, 1984. The near celebrity status that he acquired during his lifetime has multiplied since his death as the Foucault of disciplinary power has been supplemented with the Foucault of neoliberalism, biopolitics, aesthetics of the self, and the ontology of the present. These different forms of Foucauldian analysis are often grouped into three phases of scholarship that include the archeological, the genealogical, and the ethical. The first period, produced throughout the 1960s, focuses on the relationship between discourse and knowledge; the second period, developed throughout the 1970s, zeroes in on diverse structures of historically evolving power relations; and, the Foucault that emerged in the 1980s explores technologies of the self or the work of the self on the self. This well-recognized periodization highlights the triangulated structure of associations among knowledge, power, and subjectivity that animated his work. Because a number of decentered relations, something he called governmentality, are woven through everyday experience, Foucault questioned the assumption that communication takes place between autonomous, self-aware individuals who use language to negotiate and organize community formation and argued instead that this web of discourse practices and power relations produces subjects differentially suited to the contingencies of particular historical epochs. Although a critical consensus has endorsed this three-part taxonomy of Foucault’s scholarship, the interpretation of these periods varies. Some view them through a linear progression in which the failures of one moment lay the groundwork for the superseding moment: his discursive emphasis in the archeological phase gave way to his emphasis on power in the genealogical phase which, in turn, gave way to his focus on subjectivity in the ethical phase. Others, such as Jeffrey Nealon, understand the shifts as “intensifications” (p. 5) wherein each phase tightens his theoretical grip, triangulating knowledge, power, and subjectivity ever more densely. Still others suggest that the technologies of the self that undergird Foucault’s ethical period displace the leftist orientation of his early work with a latent conservatism. Regardless of where one lands on this debate, Foucault’s three intellectual phases cohere around an ongoing analysis of the relationships among knowledge, power, and subjectivity—associations at the heart of communication studies. Focused on how different subjects experience the established “regime of truth,” Foucault’s historical investigations, while obviously diverse, maintain a similar methodology, one he labeled the history of thought and contrasted with the history of ideas. As he conceives it, the history of ideas attempts to determine the origin and evolution of a particular concept through an uninterrupted teleology. He distinguishes his method, the history of thought, through its focus on historical problematization. This approach explores “the way institutions, practices, habits, and behavior become a problem for people who have certain types of habits, who engage in certain kinds of practices, and who put to work specific kinds of institutions.” In short, he studies how people and society deal with a phenomenon that has become a problem for them. This approach transforms the narrative of human progress into a history broken by concrete political, economic, and cultural problems whose resolution requires reconstituting the prevailing knowledge–power–subject dynamics. Put differently, Foucault illuminates historical breaks and the shifts required for their repair. Whereas the history of ideas erases the discontinuity among events, he highlights those differences and studies the process by which they dissolve within a singular historical narrative. Glossing his entire oeuvre, he suggests that his method can address myriad concerns, including “for example, about madness, about crime, about sex, about themselves, or about truth.” An overarching approach that intervenes into dominant narratives in order to demonstrate their silencing effects, the history of thought undergirds all three of Foucault’s externally imposed periods. Each period explores knowledge, power, and subjectivity while stressing one nodal point of the relationship: archeology stresses knowledge formation; genealogy emphasizes power formation; and the ethical period highlights subject formation. This strikingly original critical approach has left its mark on a wide range of theorists, including such notable thinkers as Gilles Deleuze, Giorgio Agamben, Michael Hardt, Antonio Negri, Donna Haraway, and Judith Butler, and has influenced critical communication scholars such as Raymie McKerrow, Ronald Greene, Kendell Phillips, Jeremy Packer, and Laurie Ouellete.