Over the last 30 years, a substantial number of publications have attempted to conceptualise the ways in which teachers carry out inquiries in order to affect changes in educational practice. A number of different psychological models have been applied to the study of teachers' activities as inquirers, including models focusing on teachers' professional development, socio-constructivist models of teacher thinking and teacher learning models. The aim of this article is to provide a more comprehensive, in-depth conceptualisation of teacher inquiry by using the central concepts of dialogical self theory and by establishing a closer relationship between teacher identity and individual teacher inquiry. We begin by defining the notions of teacher inquiry and teacher identity and then go on to describe dialogical self theory and how this approach can be applied to the description of the teacher-inquirer identity. We conclude this position paper with a detailed example in the form of a single case study illustrating how teachers' identity as inquirers can be analysed, and we offer some reflexions about potential future research in this new area of study.