By applying a framework of poststructural discursive studies and theoretical ideas of feminist poststructuralists, my doctoral thesis investigates how teachers’ professional identities have been discursively constructed in ECEC policies and practice in Aotearoa New Zealand over the last two decades. The study draws on discourse analysis of influential policy documents and transcript texts from group and individual interviews with teachers, professional leaders and managers from both community-owned and for-profit ECEC services. Research findings illustrate that the Aotearoa New Zealand ECEC has been torn between tensions created through an interplay of divergent and opposing discursive windows, which set a powerful context for constructions of complex, contradictory and fluid teachers’ professional identities. The study argues that discursive windows of enterprise, economic investment and vulnerability have promoted competition, individualism, entrepreneurship and social-intervention emphases in the sector, and frequently overpowered discourses of collectivism, collegiality, and empowerment, in which democratic education, teachers’ activism and professionalism have been rooted. The study advocates for the advocate-activist early childhood profession and teaching professionals who can bring in a much needed paradigm shift in the contemporary context of ECEC. It is hoped that this research contributes to an understanding of discourses that can strengthen capacity for constructing advocate-activist teachers’ identities at times when the market drives teachers’ work, requiring them to favour for-profit and enterprise interests over the wellbeing of children, families and community.