Dementia is a global health priority. Governments across the world are developing policy and planning services to manage the rapid rise in prevalence. We need to do the same in New Zealand but, to date, we have only extrapolated from other countries’ statistics and therefore do not have a clear idea of the true extent and impact of dementia both overall and, in particular, in Maori and Pacific people who are likely to be at greatest risk. A dementia prevalence study that represents all major ethnic groups in NZ is needed to (1) measure the true extent of dementia in NZ; (2) examine the risk factor profiles in each ethnic group; (3) measure the burden on family caregivers, and (4) determine the economic impact of dementia on families and on society. Our proposed research will test the feasibility of conducting a full-scale national NZ prevalence study of dementia.