Introduction A case study, it must be said at the outset, is not itself a research method nor the equivalent of one: it employs methods and techniques in the investigation of an object of interest. Given that case studies typically offer instances of the use of several methods for one piece of research, they are discussed in this penultimate chapter which leads directly to a consideration of multi method projects. As we shall see, the notion of a 'case' is in many ways quintessentially naturalistic, though not exclusively so, notwithstanding Cohen and Manion's assertion that 'present antipathy towards the statisticalexperimental paradigm has created something of a boom industry in case study research' (1989: 125). Case studies can range from large-to small-scale, though it is particularly at the more 'micro' end of the spectrum that they are arguably most appropriate for teacher-generated research. They have an important role to play in action research, whether for personal or wholeschool development (Elliott, 1991). Closer to our own professional concerns here, they are a very suitable format for studies of language learning. In sum, case studies have a good deal of potential, but are also somewhat problematic in both principle and practice, especially from the point of view of the single case and the wider value of such a study.