An unavoidably ideological frame of reference in Writing across the Curriculum (WAC) exists and an unavoidably political job must be undertaken if Writing across the Curriculum is to escape being the handmaiden to the so-called content disciplines. Despite this, many teachers who work in the field do not see their task as emerging from a distinct ideological framework. Writing instructors must understand the conceptions about the nature of writing that are held by professionals in various disciplines. Recently, a number of studies have centered on the texts and writing processes of such professionals. A survey looking at the past five years of two scientific and engineering journals demonstrates a lively interest in how to teach discipline-specific writing skills, and this paper relates that survey to the goals and values of Writing across the Curriculum. Writing is a social act manifesting ethical character, a way of making meaning, but these assumptions currently favored by many writing instructors may not be shared by teachers of other disciplines. Examples from engineering and chemistry educators show contradictory notions about writing. Writing instructors must promote an understanding of the ways knowledge is formulated not through systematic methods of extracting it from the world, but through social discourse, which is an ideological task. (Some sample comments about writing from other disciplines are appended.) (HB)