Brumfit's definition provides a useful starting point for this book, and in the remainder of this chapter we will discuss the two basis questions that this definition raises but does not answer: what 'real-world problems' are applied linguists interested in, and how do they go about investigating them?
Before moving on to consider these questions in detail, however, we first need to deal with an even more fundamental question about applied linguistics: what kind of' applied' subject is it?