Introduction This chapter looks at the use that can be made of more or less simple counting techniques by language teachers doing research. It also gives some background to those techniques to harness the considerable power of numerical analysis in describing and interpreting many kinds of data. It also attempts to uncover some of the assumptions of numerical methods, which, as we saw in Chapter 4, are not shared by all the approaches to research covered in this book. The chapter that follows then takes a brief look at the notion of experimentation to establish what might be useful to the readers of this book from that approach to research. Neither chapter can act as a comprehensive manual for numerical techniques; for that the reader is referred to books such as Hatch and Farhady (1982), or Woods et al. (1986).