Multidimensional analysis (MDA) is a methodological approach used to describe the underlying three-way functional relationship between situational characteristics, linguistic structures, and communicative function. The MDA approach was pioneered by Biber (1988), who used it to describe linguistic variation in spoken and written English in terms of linguistic features co-occurrence. In recent years, the MDA approach has experienced considerable methodological growth. This chapter begins with an overview of five MDA studies that played a pivotal role in the historical development of the MDA approach through the introduction of novel methods, applications, and findings. In this overview, the chapter focuses on the novel aspects of each study and the impact that it had on the field. It then discusses the current methodological state of the art, focusing on recent innovative developments occurring at three crucial stages of an MDA: selection of variables for analysis, selection of lexico-grammatical tagger, and selection of the appropriate statistical technique. The chapter concludes with a case study representing the current state of the art in MDA research.

The chapter’s focus is on the effect of task design and implementation conditionson fluency, including task design, implementation conditions and the role of interlocutors. The intention is to highlight the value of adapting research and teaching to use tasks for promoting fluency in real-world communication, taking account of pragmatic demands and cultural norms. We suggest ways in which tasks can be better used to investigate fluency, not only from an information processing perspective, but through an interactional lens, exploring speakers’ communicative strategies in fulfilling listeners’ expectations and communicative needs.