Health services research has been dominated by the biomedical paradigm and positivism, and the funding cultures of biomedicine have dictated the choice of method used by researchers. Social science paradigms, however, have been recognised as increasingly important within health services research and both quantitative and qualitative methods are accepted as appropriate. Older people with dementia have usually been excluded from or marginalised in studies about dementia because of traditional assumptions about the ability or appropriateness of people with dementia to act as participants or respondents. The choice of research method should be driven by theory and not by ideological or political prescription. Theory-driven pluralistic approaches to method will facilitate participation of people with dementia in research through the valuing of personhood. There are no unique methodological challenges in researching dementia. Rather, the complex nature of dementia and dementia care highlight the methodological challenges of investigating complex social phenomena.