Background : The integration of nurse practitioners into primary healthcare settings is highly complex, yet it has not been extensively studied with regard to broader socioprofessional changes occurring in health care.Objective : This study sought to examine the integration and negotiation of the role of nurse practitioners in interprofessional primary healthcare settings.Method : A critical ethnography framed by actor-network theory and Foucault's concepts of discourse and power was conducted in three different primary healthcare models in which semi-structured interviews (n=23 nurse practitioners), direct observation, and document analysis were performed.Results : Organizational aims, practice standards, nurse practitioners' right to self-determination, collaborative dynamics with physicians, and patient management were identified as integration factors that produced greater instability, needs for negotiation, and professional, identity, and moral difficulties for nurse practitioners.Discussion : The findings from this study challenge the widespread perception that the role of nurse practitioners lacks clarity and enable a renewed understanding of their integration process in primary healthcare settings.