We shall see in subsequent chapters of this part of the book that research by teachers, both in practice and in its theoretical underpinnings, is complex and indeed controversial, directly impinging on such fundamental research questions as validity, generalizability and the nature of its contribution to a wider store of knowledge. These chapters will also comment more fully on derivations from research in anthropology and social science in particular. First, however, it is necessary in this chapter to show that research by teachers is embedded in a number of broader traditions in education, and in the course of the present discussion we shall be concerned with the much-mentioned question of the relationship between 'theory' and 'practice' and the 'relevance' of the former; with the nature and role in research of teaching conceived of as 'action', and with the possibilities inherent in teacher research for effecting educational change.