Although often associated with older age, loneliness and social isolation are not well understood in terms of their prevalence, risk and protective factors. Evidence suggests that only a minority of community-dwelling older people are "severely" lonely or isolated, however a number of factors need to be considered to fully understand the extent and significance of the problem. Community-based studies have identified a variety of risk factors for loneliness/isolation including widowhood, no (surviving) children, living alone, deteriorating health, and life events (eg, loss and bereavement). Having a confidant has been identified as a protective factor for loneliness. However, evidence is often unclear or inconclusive, especially within residential settings. We identified the need to conduct more residential care-focused research; the importance of addressing a variety of methodological concerns; and the need for practitioners to develop intervention programs that are appropriately targeted, evidence-based and evaluated.