In this chapter there is a distinct shift from examining lexical items at the level of the orthographic ‘word’ or in the patterns which occur in fixed expressions towards a consideration of lexis in larger units of language organization. It is also here that greater differentiation than in previous chapters is made between spoken and written discourse. Thus, the operations of lexis will be explored in written discourse across the boundaries of the sentence and in spoken discourse across such boundaries as conversational turns. The terms text and discourse will be used interchangeably in this chapter to refer to these larger organizational units of language, although distinctions between the terms can and have been made (see Stubbs, 1983, pp. 9-11, who also discusses issues in the appropriate collection and analysis of naturally occurring data). We should also note that ‘discourse’ is used with systematic ambiguity to refer to (1) a complete stretch of naturally occurring language – discourses, and (2) the theoretical level at which stretches of spoken and written language are analysed – discourse. In the first of these uses, note that ‘discourse’ takes a plural.