This contribution employs an integrated approach to the investigation of the form and function of the theme zone in English media discourse giving particular attention to the communicative genres of political interview and editorial. It is informed by a function-based outlook on language (Givón, 1993; Halliday, 1994) and a sociopragmatic framework (Fetzer, 2004; Gumperz, 1992) supplementing and refining function-based results with context-based parameters, that is production format and recipient design, genre and media frame. The first part examines the connectedness between a theme zone and its function in discourse considering especially its definitions and delimitations. Because of its forward- and backward-pointing potentials, the theme zone is of key importance for the construction of discourse coherence, where it may signify a continuation, respectively a discontinuation, in the flow of discourse regarding topic, force or attitude. For this reason, it is assigned the status of a contextualization cue (Gumperz, 1977). The second part classifies theme zones into marked and unmarked configurations with respect to (1) genre, (2) mode and (3) sequential status. The third part systematizes the results and demonstrates that a context-based investigation of theme zones adds further evidence for the dialogical nature of language and language use. © 2008 Elsevier B.V. All rights reserved.