This article analyses the privatization of Early Childhood Education and Care (ECEC) provision in Norway between 1987 and 2020. My analytical framework combines theories of structured organizational fields and gradual institutional change to investigate how the scope and field position of private ECEC providers have evolved during this period. Based on an analysis of official policy documents, I illuminate how ECEC quality enhancement has gradually been institutionalized as the common, legitimizing endeavour of the ECEC provision field by means of coercive isomorphic pressure. Along with increasing regulation of working conditions, this has altered the meaning of private ECEC provision. Both the scope and field position of private provider organizations have evolved accordingly. Currently, small providers and larger provider corporations face different sets of legitimacy challenges, resulting in a conflict of interests. Tensions between these groups are likely to fuel ongoing field dynamics that are capable of yielding institutional stability as well as change. My analysis contributes towards building a more comprehensive theoretical framework for organizational fields by illuminating the interplay between coercive isomorphic pressure and organizational characteristics within a structured field.