The feeding problems of demented elderly people are well documented and the need for research into the assessment of feeding difficulty and intervention by nurses has been raised The present paper reviews the literature in this area of care and outlines the problems which exist in attempting to investigate the feeding difficulty of demented patients Demented elderly people display a range of behaviours related to feeding including excessive eating in the early stages of dementia and then difficulty with feeding, refusal to eat and, finally, inability to self-feed at all The problems with research in this area revolve around the issue of measurement of feeding difficulty There are problems in deciding what to measure and in how measurements should be made which are clinically meaningful A possible strategy for investigating the feeding difficulty of demented elderly patients is suggested which includes the design of a tool for measurement and the application of single-case studies Any tool which is used for measurement should enable researchers, in the first instance, and then clinicians to categorize the feeding difficulty of individual patients Moreover, such a tool should also be sufficiently sensitive to respond to change in feeding ability The single-case methodology is considered to be the most ethically and statistically appropriate for research with this particular group of patients