This chapter looks at the research approaches that have been used to study classroom talk since the start of the 20th century before going on to consider how a greater focus on implementing a dialogic pedagogy has emerged since the start of the 21st century. It considers what the research is telling about the kinds of professional conditions needed for teachers if they are to successfully implement a dialogic pedagogy in the classroom. With the growing body of research into a dialogic pedagogy has come a range of terms for describing the pedagogical approaches. During the 1990s, however, the popularity of systematic observation in researching classrooms started to decline. This was largely due to the development of sociocultural research and linguistic and ethnographic approaches to researching classroom practices. International research into classroom interaction and discourse suggests the initiation–response–feedback/evaluation structure is a universal feature of classroom talk across all levels of education from primary school through to higher education.