Using the systemic functional model as their point of departure, the papers in the present volume consider the formal criteria of Subject and Theme and the relations between the two concepts in a wider context by relating them to the interpersonal and textual metafunctions of language. By contrast with the current linguistic approaches, the primary focus here is neither simply on formal recognition criteria nor on the relation of these elements to each other; instead, the notions of Subject and Theme are examined from the point of view of their function in the economy of discourse, with studies of their significance in English and French, as well as in a range of non-Indo-European languages.