Dialectic of Enlightenment (German: Dialektik der Aufklärung), is the core text of Critical Theory explaining the socio-psychological status quo that had been responsible for, what the Frankfurt School considered, the failure of the Enlightenment.

Written by Frankfurt School philosophers Max Horkheimer and Theodor W. Adorno, the book made its first appearance in 1944 under the title Philosophische Fragmente by Social Studies Association, Inc., New York. A revised version was published in 1947 by Querido Verlag in Amsterdam with the title Dialektik der Aufklärung. It was reissued in 1969 by S Fischer Verlag GmbH. There have been two English translations: the first by John Cumming (New York: Herder and Herder, 1972) and a more recent translation, based on the definitive text from Horkheimer's collected works, by Edmund Jephcott (Stanford: Stanford University Press, 2002). It has had a major effect on 20th century philosophy, sociology, culture, and politics, inspiring especially the New Left of the 1960s and 1970's.

The work contains:

• "The Concept of Enlightenment";
• "Excursus I: Odysseus or Myth and Enlightenment"
• "Excursus II: Juliette or Enlightenment and Morality"
• "The Culture Industry: Enlightenment as Mass Deception" (in which they prefigure Marshall McLuhan's thesis that "the medium is the message")
• "Elements of Anti-Semitism: Limits of Enlightenment"
• "Notes and Drafts"