This paper argues that children who have been deemed to be 'at-risk' need specialist intervention and that the Irish public health nurse (PHN) cannot provide this intervention. It is further argued that a failure to acknowledge and act on this is placing children at further risk and it is suggested that the mismatch between actual and perceived (or expected) roles leads to practices which undermine rather than support child protection. The PHN's remit in protecting children is situated within the following contexts: the variety of client groups with whom the PHN works, overall provision of child health services in the community, her education and training, and primary, secondary and tertiary protection of children. Two recent reports on enquiries into the failure of the services to protect children living with their families are used to explore the discontinuity. Existing evidence on how personnel involved (directly and indirectly) in community care services perceive or understand the PHN's role in child protection is described in the context of what the PHN's role actually is. The evidence suggests that the PHN fulfils a range of prescribed roles but that there is a perception or expectation among other service providers that she is also fulfilling additional roles. The paper concludes by suggesting some possible solutions to this discontinuity with a view to improving child protection services.