Language is the tool of tools, essential to our identities as individuals and as a species. All living languages change continuously, and people are responsible for that change, primarily to express identity and build relationships (Trask, 2010). This thesis is about language, English Language Teaching (ELT), and in particular the evolving identities and development of Speakers of Other Languages Teaching English (SOLTEs). It is presented against a contemporary backdrop of globalisation and complex forces of sociocultural and educational transformation, which influence the field of language and identity research. English in the early 21st century is indisputably the world's Lingua Franca (Ostler, 2010), in that billions of people use it alongside thousands of other languages: a growing majority of its speakers are thus defined as 'non-native'. There is a similar pattern in the proportions of teachers: the majority are local to their professional context, share the first language of their students, and work in mainstream school systems. Crystal (2003) expresses an ideal balance between multilingualism and a globally-intelligible world language. This also implies the presence of multilingual, multicompetent language practitioners, and it is these people who stand at the centre of the study. The thesis addresses the following related research questions: 1. What does it mean for Speakers of Other Languages Teaching English (SOLTEs) to say: 'I am an English teacher'? 2. How do these multilingual, multicultural teachers develop their identities and what influences their professional practice and beliefs? 3. What are the implications of the globalisation of English for the field of English Language Teaching, and the impact on the position of SOLTEs? In exploring these questions, the study aims to discover more about these ELT practitioners' attitudes towards the definition of their subject, and the development of their own multiple identities in relation to the language they teach, its learning and use. For example, do teachers see language as essentially a body of knowledge to be taught and learnt, or a social practice, a set of skills to be acquired and developed? To what extent does their own language learning experience condition their beliefs and teaching approach? How do they see themselves in terms of professional competence and personal confidence? In short, who do they think they are? The study uses semi-structured interviews and online discussion with a small group of six teachers based in various European ELT contexts, including the UK. The research methodology is participative and interpretative, designed to be relevant to the central questions and the individuals involved. An inductive approach to qualitative data analysis is adopted, where meaning is uncovered and categorised through a process of iterative engagement with the raw narrative texts produced with the participants. The aim is to present a fuller picture and tell a credible and interesting story. In answer to the question 'Who do you think you are?' the participants claim both competence and confidence as English language teachers, yet also express self-doubt and reservations towards a still-powerful 'native' model that they themselves increasingly question. The implications of this study suggest that the field of ELT needs to move away from debates on 'nativeness', 'ownership' and idealised norms, towards notions of 'beyond-native' language competence, a 'multilingual principle' for teaching and learning, and more appropriate teacher education programmes. Pedagogical targets for all living languages also change continuously, as do people's local communicative needs and identity claims, in a globalised world where multicompetent teachers can act as role models for their learners. If these new realities are recognised, a pedagogy for the 21st century can evolve which embraces teachers' and learners' multiple identities, as part of Crystal's (2003) ideal world of mutual understanding, where English in its infinite varieties and idiolects can sit alongside all other languages.