Despite the importance of early diagnosis of dementia, little is known about the factors underlying help-seeking in relation to signs of the condition. In this pilot study, we aimed to examine the potential utility of the common sense model (CSM) of illness representations for understanding lay perceptions of dementia and predicting intentions to seek help in relation to possible signs and symptoms. A secondary aim was to develop a measure of (dementia-related) illness representations as a tool for future research. After reading a vignette describing a "relative" with mild or moderate dementia, participants (N = 118) completed measures of illness representations and help-seeking intentions. Analyses compared perceptions of the mild and moderate vignettes and determined the extent to which illness perceptions differentiated between alternative forms of help-seeking (e.g. seeking professional help vs. help from family members). Results indicated that cognitive deficits were more readily identified as dementia than non-cognitive symptoms; these were commonly attributed to stress or depression. Participants were more likely to indicate an intention to seek professional help if they identified the problem in the vignette as dementia, perceived symptoms as severe, as having serious consequences and as likely to be permanent, but less likely to do so if they identified the problem as stress or attributed symptoms to psychological causes. Our preliminary data suggests that help-seeking may be prevented by inaccurate illness representations or misattribution of symptoms. The CSM may provide a useful framework for understanding perceptions of dementia symptoms and for informing help-seeking pathways.