In this paper, the authors explore the latest manifestation of backward curriculum discourse, namely, a theory of "backward" unit design. The authors view this "backward" curriculum discourse as foundationally positivist and/or structural, yet they adopt a poststructural point of view. This theoretical undergirding makes it possible to rethink underlying, taken for granted assumptions. Their focus is on illuminating the potential problems of "structure-based," formulaic prescriptions of curriculum theory. Here, the authors situate "backward" curriculum discourse in the context of curriculum history and introduce its basic ideas and structures. They then continue their deconstruction by examining Wiggins and McTighe's attempts to "understand understanding" and then detail the key role and function of assessment underpinning this "backward" discourse. They present three grand narratives of "backward" discourse and critically discuss the myth of such grand narratives in terms of the problem of instrumental rationality, the hidden pitfall of teachers' overemphasized role on assessment, and a lack of cultural sensitivity. (Contains 3 notes and 1 table.)