Introduction 'Observation', as it stands, is a monolithic label, a broad and even amorphous umbrella term subsuming many and varied purposes and interpretations. Hopkins (1993), for example, gives a positive sense of this breadth of application by describing it as a 'pivotal activity' with a crucial role to play in classroom research, teachers' personal-professional growth, and school development as a whole. Observation with its associated techniques is also often embedded in a larger-scale research plan as one method among others, when perhaps a variety of data sources is appropriate. Here, however, we take it as by and large discrete, returning to it in the final chapter in the discussion of ways in which methods might be used in conjunction with each other.