With a growing older population, and depression affecting a considerable proportion of care home residents, it is imperative that effective methods of treating depression in this population are found. Systematic reviews of research into reminiscence as a treatment for depression have produced contradictory results, partly due to the lack of a standardised approach to reminiscence in the original studies. A literature review was therefore carried out to answer the question: ‘What factors influence the effectiveness of reminiscence approaches in treating and preventing depression in residents of care homes for older people?’ Six electronic databases were searched using the terms ‘Reminiscence AND Depression’. After inclusion and exclusion criteria had been applied, a total of ten papers were critically appraised. Two of these were subsequently excluded due to serious weaknesses in methodology, leaving eight papers for analysis and synthesis. From these eight papers, five key themes were discerned, leading to insights into factors which assist and limit the effectiveness of reminiscence. These include the social aspects of reminiscence, together with opportunities for self-expression, sharing of emotions, and developing trusting relationships with group leaders. Reminiscence was found to be a particularly useful activity for care home residents because of combining a number of different benefits in one activity. However, a cautionary note is sounded about reminiscence work being undertaken by untrained staff who may have little appreciation of the dangers of reminiscing for some clients.