IntroductionThose aged 80 years and over are the fastest‐growing sector of the Australian population but are often excluded from research. Oldest old people living alone, in disadvantaged neighbourhoods, and with ill health or dementia, face additional barriers that may hinder their participation in research.MethodsThis paper contributes timely critical commentary on methodological and ethical approaches to engaging under‐represented people in research. We draw on our experiences and reflections from a study of social exclusion of people aged 80 years and older living alone in government housing in Melbourne, Australia.Results and DiscussionWe suggest key factors to facilitate representation of this population group in future research. These factors include using doorknocking to gain access, cultivating trust with participants and gatekeepers, and conducting face‐to‐face home interviews. We also interrogate ethical and safety issues for researchers and oldest old participants including the potential for informed consent protocols to exclude this population group.ConclusionTo avoid unintentionally excluding the oldest old, researchers need to consider older persons' self‐determination and advocate for methods that ensure oldest old perspectives inform future healthy ageing planning and reduce possible health and well‐being inequities.