This paper argues that Critical Theory can, and should, take an inter-cultural turn, through which the contemporary challenges posed by cultural pluralism be faced. To begin, I attempt to demonstrate the paucity of Critical Theorists' engagement with issues of cultural alterity, reviewing three stages in the history of this encounter: Horkheimer and Adorno's interest in the relationship between myth and reason; Habermas's evolutionary theory of rationality; and, more recently, Honneth's framework of social recognition. Thus, in a first instance, the flawed or underdeveloped character of Critical Theory's cross-cultural sensibility will be stressed. The second part of the paper indicates some of the paths leading to a more cross-culturally sensitive Critical Theory. I thus call for the incorporation of some of the insights of a French stream of 'ethnological' social theory. Drawing on the work of Levi-Strauss and Foucault, the paper strives to demonstrate how the 'ethnologization' of Critical Theory enables the defamiliarization and radical interrogation of Cartesian rationalism.