Approximately 5% of older people, those aged 65 years and over, in developed countries live in care homes and these represent the frailest and most vulnerable members of this population group. Levels of morbidity, especially dementia and cognitive impairment, are high, making it challenging to conduct research with these population groups. Loneliness is a debilitating condition with important negative outcomes in terms of both quality of life and wider health outcomes. The prevalence of severe loneliness among older people living in care homes is at least double that of community-dwelling populations: 22–42% for the care population compared with 10% for the community population. However, the evidence-base for the care home group is tentative as it is based upon a very limited empirical base of only five studies. This review failed to identify compelling evidence for the effectiveness of interventions to remediate loneliness in care home populations.