Abstract: The aim of this research was to explore surveillance discourses within New Zealand child health nursing and to identify whether surveillance practices have implications in this context for power relations. Five experienced and practising Plunket nurses were each interviewed twice. The texts generated by these semi-structured interviews were analysed using a Foucauldian approach to critical discourse analysis. In contrast with the conventional view of power as held and wielded by one party, this study revealed that, in the Plunket nursing context, power is exercised in various and unexpected ways. Although the relationship between the mother and the nurse cannot be said to operate as a partnership, it is constituted in the nurses' discourses as a dynamic relationship in which the mother is actively engaged on her own terms. The effect of this is that it is presented by the nurses as a precarious relationship that has significant implications for the success of their work.