Rosenblatt (1978), Widdowson (1979), and others have argued persuasively that successful reading is an act of creation: the reader creates meaning through the interaction with a text. In this view, the meaning of a text does not reside in a fixed, static form frozen within the words on the page. Rather, it emerges anew in each encounter of a reader with a text. A text, then, does not contain meaning as such but, as Widdowson suggests, potential for meaning, which readers, both native and nonnative, will realize in varying degrees. This ability to create meaning (what is usually referred to as comprehension) depends critically on, and in fact may be said to presuppose, another kind of interaction – that of various types of information the reader brings to the reading task and information available in the text itself. (See Grabe, Chapter 4 of this volume, for a full treatment of the various senses of the term interactive.) Eskey (1986) identifies two categories of knowledge that must interact if there is to be “full, or at least native-like, comprehension of written texts” (p. 17): knowledge of form and knowledge of substance. Formal knowledge includes recognition of graphophonic, lexical, syntactic/ semantic, and rhetorical patterns of a language; knowledge of substance encompasses cultural, pragmatic and subject-specific information.