This thesis examines the ways in which five bilingual teachers use their two languages in English-medium early childhood services in the Auckland region. Questions regarding the possible mediation of bilingual identities for teachers and children created a further interrogation of teachers' 'lived experiences' of bilingual activity. The research, informed by critical multiculturalism, used a qualitative methodology and Narrative Inquiry that employed a spiral discourse or 'conversation' approach for data collection. The collaborative insights from participants and researcher became the foundation for further analysis. Findings revealed that bilingual teachers in the absence of government policy, worked powerfully to construct a critical bilingual praxis to counter deficit discourses of bilingualism in Aotearoa/New Zealand. Teachers' 'lived experiences' illustrated their deep knowledge of bilingualism and the use of two languages as critical linguistic and cultural resources for teaching and learning. As trusted agents for the educational and home language communities, 'doing self as bilingual teacher' worked cogeneratively to mediate bilingual identities for themselves and for children.