Nurse prescribing is gradually being implemented across a range of areas in healthcare. This paper examines the context of prescribing for mental health problems and discusses the issues relating to nursing and some of the broader matters such as the effectiveness of medication for mental health problems, the economics of mental illness and more general workforce issues. Mental health nurse prescribing obviously presents some significant research opportunities that should be seen within the settings of the Medical Research Council's framework for assessing complex health interventions (Campbell et al., 2000). The paper also considers some of the challenges of undertaking a randomised controlled trial for a topic within what Nancy Woolf (2000) describes as a 'socially complex service context'. Such a context requires the research team to consider a number of potential confounds. The paper concludes by suggesting some ways that such sources of confound be minimised.