Abstract Depression in the elderly, particularly those with chronic physical health problems, is a common, but complex problem. In this paper we review the research literature on both the epidemiology and management of depression in the older medical patient. After a general overview of depression in the elderly, we discuss some of the particular issues relevant to depression and co-morbid physical illness amongst elderly patients. Depression can be difficult to diagnose in medically unwell older adults, particularly when there is substantial overlap in symptomatology. The epidemiology and evidence base for the treatment of depression in a number of chronic health problems common in an older adults population are then discussed, specifically cardiac disease, cerebrovascular disease, cancer, chronic kidney disease, chronic obstructive pulmonary disease, and Parkinson's disease. For many of these conditions there is emerging evidence that treatments can be effective in reducing depressive symptoms. However, these potential benefits need to be balanced against the often-increased risk of adverse events or interactions with medical treatments. Although co-morbid depression is consistently associated with poorer medical outcomes, there is limited evidence that standard anti-depressive therapy has additional benefits in terms of physical health outcomes. Collaborative care models appear particularly well suited to medically unwell older adult patients, and may provide more generalised benefits across both mental and physical health measures.