The aim of this study was to critically examine the impact of nursing research on the development of health care policy using UK health visiting research as an example. We used established methods to evaluate research impact. This included a documentary review of over 30 policy documents, citation analyses on 19 papers and interviews with health visiting researchers. Although there were examples of policy documents being informed by health visiting research it was not always clear what role research had played in the development of recommendations. Information from researchers provided examples of local, national and international impact, although the extent to which papers may have impacted upon policy was less clear from the citation analyses. Many of the UK studies cited in policy documents were qualitative, observational or reflexive and a lack of evaluative research, in particular randomised controlled trials and other controlled evaluations, may limit the impact of health visiting research on health care policy in the UK. There is evidence that health visiting research has influenced health care policy but this has been limited and there is a need for more research to underpin and inform the role of the health visitor.